Cardiac Biomarker Responses Following High-Intensity Interval and Continuous Exercise: The Influence of ACE-I/D Gene Polymorphism and Training Status in Men

This study aimed to investigate the relationship between pre and post-exercise cardiac biomarker release according to athletic status (trained vs. untrained); and to establish whether the I/D polymorphism in the ACE gene had an influence on cardiac biomarkers release with specific regard on the influence of the training state. We determined cTnI and NT-proBNP in 29 trained and 27 untrained male soccer players before and after moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) running tests. Trained soccer players had higher pre (trained: 0.014±0.007 ng/mL; untrained: 0.010±0.005 ng/mL) and post HIIE (trained: 0.031±0.008 ng/mL; untrained: 0.0179±0.007) and MICE (trained: 0.030±0.007 ng/mL; untrained: 0.018±0.007) cTnI values than untrained subjects, but the change with exercise (ΔcTnI) was similar between groups. There was no significant difference in baseline and post-exercise NT-proBNP between groups. NT-proBNP levels were elevated after both HIIE and MICE. Considering three ACE genotypes, the mean pre-exercise cTnI values of trained group (DD: 0.015±0.008 ng/mL; ID: 0.015±0.007 ng/mL; II: 0.014±0.008 ng/mL) and their untrained counterparts (DD: 0.010±0.004 ng/mL; ID: 0.011±0.004 ng/mL; II: 0.010±0.006 ng/mL) did not show any significant difference. To sum up, noticeable difference in baseline cTnI was observed which was related to athletic status, but not ACE genotypes. Neither athletic status nor ACE genotypes seem to affect the changes in cardiac biomarkers in response to HIIE and MICE, indicating that the ACE gene does not play a significant role in the release of exercise-induced cardiac biomarkers indicative of cardiac damage in Iranian soccer players.

Effect of resistance training plus enriched probiotic supplement on sestrin2, oxidative stress, and mitophagy markers in elderly male Wistar rats

This study aimed to determine the effects of resistance training combined with a probiotic supplement enriched with vitamin D and leucine on sestrin2, oxidative stress, antioxidant defense, and mitophagy markers in aged Wistar rats. Thirty-five male rats were randomly assigned to two age groups (old with 18-24 months of age and young with 8-12 weeks of age) and then divided into five groups, including (1) old control (OC: n = 5 + 2 for reserve in all groups), (2) young control (YC: n = 5), (3) old resistance training (OR: n = 5), (4) old resistance training plus supplement (ORS: n = 5), and old supplement group (OS: n = 5). Training groups performed ladder climbing resistance training 3 times per week for 8 weeks. Training intensity was inserted progressively, with values equal to 65, 75, and 85, determining rats' maximal carrying load capacity. Each animal made 5 to 8 climbs in each training session, and the time of each climb was between 12 and 15 s, although the time was not the subject of the evaluation, and the climbing pattern was different in the animals. Old resistance plus supplement and old supplement groups received 1 ml of supplement 5 times per week by oral gavage in addition to standard feeding, 1 to 2 h post training sessions. Forty-eight hours after the end of the training program, 3 ml of blood samples were taken, and all rats were then sacrificed to achieve muscle samples. After 8 weeks of training, total antioxidant capacity and superoxide dismutase activity levels increased in both interventions. A synergistic effect of supplement with resistance training was observed for total antioxidant capacity, superoxide dismutase, and PTEN-induced kinase 1. Sestrin 2 decreased in intervention groups. These results suggest that resistance training plus supplement can boost antioxidant defense and mitophagy while potentially decreasing muscle strength loss.

Are the digit ratio (2D:4D) and hand grip strength related to Parkinson disease in elderly males?

BACKGROUND

Sex hormones affect the pathogenesis of Parkinson patients and it has been suggested that gender is the most important factor in the development and progression of Parkinson's disease. Studies have shown that the second to fourth digit ratio (2D:4D) is affected by the prenatal testosterone and estrogen levels and can predict predisposition to disease. In addition, decreased muscle strength in people with Parkinson's has been repeatedly reported. Hand grip strength (HGS) is a suitable measure to evaluate the musculoskeletal system among the elderly and it is considered as an indicator of the overall strength of the body. This study aimed at investigating the relationship between Parkinson's disease and HGS and 2D:4D ratio.

METHODS

In this study 117 elderly men with Parkinson disease (mean age of 61.66 ± 11.28 years) and 156 healthy control subjects (mean age of 61.86 ± 6.29 years) participated. After determining the level of disability of Parkinson patients by a neurologist (level of disability in the range of 1-4), anthropometric indices (height, weight, length of the second and fourth fingers) and maximum HGS were measured.

RESULTS

Although 2D:4D ratios (right and left hand) of male patients with Parkinson's disease were higher than those of healthy males, this difference was not statistically significant (P = 0.12, P = 0.40; respectively). Conversely, HGS for the right and left hands of Parkinson patients were significantly lower than those of healthy males (P = 0.02, P = 0.03; respectively). The results showed a significant negative relationship between Parkinson disease and the right and left HGS (R = -0.16, P = 0.005; R = -0.17, P = 0.003; respectively). Parkinson disease had no significant relationship with 2D:4D of the right hand, left hand, mean finger ratio and D_R-L 2D:4D (P > 0.05). The regression results showed that the right and left HGS were not able to predict Parkinson disease (P = 0.25, P = 0.16; respectively).

CONCLUSION

We concluded that HGS was negatively associated with the Parkinson disease, but conversely, 2D:4D may not be a valuable biomarker of elevated risk of Parkinson in elderly males.

Associations between bio-motor ability, endocrine markers and hand-specific anthropometrics in elite female futsal players: a pilot study

BACKGROUND

The second-to-fourth digit ratio (2D:4D) has been calculated for individual athletes and sports, but it has not been investigated in futsal performance. Therefore, the aim of this study was to investigate any relationships between 2D:4D of the dominant and non-dominant hands and physical capacity performances, selected functional variables and hormone concentrations in elite female futsal players.

METHODS

Twenty-four elite female futsal players were measured for 2D:4D in the dominant (2D:4D_D) and non-dominant (2D:4D_ND) hand. The futsal specific performance test (FSPT), hand-grip strength (HGS) and aerobic power were also assessed. In addition, selected circulatory hormones were measured (estradiol, cortisol, growth hormone and insulin like growth factor-1). Pearson's correlation test was used to identify correlational relationships.

RESULTS

Total test-time and performance time (total time + penalty time) for the FSPT showed a significant correlation with 2D:4D_D (r = 0.53, p = 0.005 and r = 0.55, p = 0.003, respectively). HGS_ND also displayed a significant correlation with the 2D:4D_D (r = 0.59, p = 0.002). Aerobic power and time spent running on the treadmill also showed a significant relationship with 2D:4D_ND (both, r = 0.54, p = 0.006). Cortisol showed a significant correlation with 2D:4D_D (- 0.58, p = 0.003) and 2D:4D_ND(- 0.52, p = 0.008).

CONCLUSIONS

The measurement of 2D:4D ratio could be an important factor in determining potential performance attributes and talent identification of elite female futsal players. Further studies are needed in this area to further examine the results presented here.

Interactive effect of socio-eco-demographic characteristics and perceived physical activity barriers on physical activity level among older adults

Background

Studies examining associations of socio-eco-demographic characteristics with physical activity (PA) participation of older adults have produced inconsistent results. Perceived PA barriers may be a possible explanation for the mixed findings. Therefore, the purpose of this study was to examine the correlation of socio-eco-demographic (SED) characteristics with PA of older adults and the moderation effects of perceived barriers of PA.

Methods

Three hundred eighty-four older adults (≥ 60 years old) were recruited from public places in six different cities. Questions regarding socio-eco-demographic characteristics, PA, and perceived PA barriers were asked, in-person, by two examiners. Ordinal logistic regression models examined the association of socio-eco-demographic characteristics with subjectively measured PA, and the interactive effects of subscales of perceived PA barriers and socio-eco-demographic variables for PA outcomes.

Results

Significant main effects for PA outcomes were found for education and living status (P < 0.01) and college-educated individuals and those were living in their private houses reported higher PA. Also, 24 significant interactive effects of perceived PA barriers by socio-eco-demographic factors were found (P < 0.05). Significant moderation effects by all subscales of perceived PA barriers were observed for education and living status. The effect of age for the PA outcomes was moderated by “lack of time”, “fear of injury”, and “lack of skill”. Only “fear of injury” and “lack of time” moderated the effect of gender and marriage for outcome variable, respectively. The effect of employment was moderated by “lack of willpower”, “fear of injury”, “lack of skill” and “lack of resources”.

Conclusions

Novel evidence revealed that there are moderations by perceived PA barriers for the effect of almost all socio-eco-demographic characteristics. These findings highlight a need to consider older adults’ perspectives and perceptions, when it comes to establish policies for PA participation.

Effects of short-term betaine supplementation on muscle endurance and indices of endocrine function following acute high-intensity resistance exercise in young athletes

Objective

This study examined the effects of short-term betaine supplementation on muscle endurance, plasma lactate, testosterone and cortisol levels, and the testosterone to cortisol (T/C) ratio in response to acute resistance exercise (RE).

Method

Using a double-blind, crossover study design, 10 handball players (age ± SD = 16 ± 1 yrs) without prior-structured RE experience performed a high-intensity RE session (leg press followed by bench press; 5 sets to volitional fatigue using 80% baseline 1 repetition maximum (1RM)), before and after 14 days of either placebo (maltodextrin) or betaine (2.5 g·d⁻¹) supplementation. A 30-day washout period separated each treatment. 48 h prior to testing sessions, participants recorded their food intake and did not perform strenuous exercise. Venous blood was sampled before supplementation, and before and after each RE session.

Results

After betaine supplementation, participants performed more repetitions (p < 0.001) during the leg press (Betaine: 35.8 ± 4.3; Placebo: 24.8 ± 3.6, Cohen’s d = 2.77) and bench press (Betaine: 36.3 ± 2.6; Placebo: 26.1 ± 3.5, Cohen’s d = 3.34). Betaine resulted in lower post-exercise cortisol (Betaine: 7.6 ± 1.7; Placebo: 13 ± 3.4 µg.dL⁻¹, p = 0.003, generalized eta squared (ηG2) = 0.49) and lactate (Betaine: 5.2 ± 0.3; Placebo: 6 ± 0.3 mmol.L⁻¹, p < 0.001, ηG2 = 0.96) and higher total testosterone (Betaine: 15.2 ± 2.2; Placebo: 8.7 ± 1.7 ng.mL⁻¹, p < 0.001, ηG2 = 0.87) and T/C ratio (Betaine: 0.21 ± 0.05; Placebo: 0.07 ± 0.02, p < 0.001, = 0.82).

Conclusions

Two weeks of betaine supplementation improved upper- and lower-body muscle endurance and influenced indices of endocrine function following an acute session of high-intensity RE in adolescent handball players.

Effects of a New Form of Resistance-Type High-Intensity Interval Training on Cardiac Structure, Hemodynamics, and Physiological and Performance Adaptations in Well-Trained Kayak Sprint Athletes

This study examined the effects of a resistance-type high-intensity interval training (RHIIT) matched with the lowest velocity that elicited V.O_2peak (100% vV.O_2peak) in well-trained kayak sprint athletes. Responses in cardiac structure and function, cardiorespiratory fitness, anaerobic power, exercise performance, muscular strength, and hormonal adaptations were examined. Male kayakers (n = 24, age: 27 ± 4 years) were randomly assigned to one of three 8-wk conditions (N = 8): (RHIIT) resistance training using one-armed cable row at 100% vV.O_2peak; paddling-based HIIT (PHIIT) six sets of paddling at 100% vV.O_2peak; or controls (CON) who performed six sessions including 1-h on-water paddling/sessions at 70–80% maximum HR per week. Significant increases (p < 0.05) in V.O_2peak, vV.O_2peak, maximal cardiac output, resting stroke volume, left ventricular end-systolic dimension, 500-m paddling performance were seen pre- to post-training in all groups. Change in V.O_2peak in response to PHIIT was significantly greater (p = 0.03) compared to CON. Also, 500-m paddling performance changes in response to PHIIT and RHIIT were greater (p = 0.02, 0.05, respectively) than that of CON. Compared with pre-training, PHIIT and RHIIT resulted in significant increases in peak and average power output, maximal stroke volume, end-diastolic volume, ejection fraction, total testosterone, testosterone/cortisol ratio, and 1,000-m paddling performance. Also, the change in 1,000-m paddling performance in response to PHIIT was significantly greater (p = 0.02) compared to that of CON. Moreover, maximum strength was significantly enhanced in response to RHIIT pre- to post-training (p < 0.05). Overall, RHIIT and PHIIT similarly improve cardiac structure and hemodynamics, physiological adaptations, and performance of well-trained kayak sprint athletes. Also, RHIIT enhances cardiorespiratory fitness and muscular strength simultaneously.

Effects of Different Types of Exercise on Kidney Diseases

The effects of exercise on kidney function have been studied for more than three decades. One of the most common health issues among patients with chronic kidney disease (CKD) is a lack of physical activity, which leads to a low exercise capacity in these patients. The majority of maintenance hemodialysis (MHD) patients do not exercise at all. At each stage of dialysis, patients lose 10–12 g of their amino acids through blood sampling. Dialysis also leads to increased cortisol and circadian rhythm sleep disorders in hemodialysis (HD) patients. Studies have also reported higher C-reactive protein levels in HD patients, which causes arterial stiffness. Exercise has a variety of health benefits in these patients, including improved blood pressure control, better sleep, higher physical function, and reduced anxiety and depression. On the other hand, it should be noted that intense exercise has the potential to progress KD, especially when conducted in hot weather with dehydration. This review aimed to investigate the effects of different types of exercise on kidney disease and provide exercise guidelines. In conclusion, moderate-intensity and long-term exercise (for at least a 6-month period), with consideration of the principles of exercise (individualization, intensity, time, etc.), can be used as an adjunctive treatment strategy in patients undergoing dialysis or kidney transplantation.

Moderate Intensity Aerobic Exercise Potential Favorable Effect Against COVID-19: The Role of Renin-Angiotensin System and Immunomodulatory Effects

The coronavirus disease (COVID-19) pandemic is caused by a novel coronavirus (CoV) named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the angiotensin converting enzyme 2 (ACE2) is the cellular receptor of SARS-CoV-2, it has a strong interaction with the renin angiotensin system (RAS). Experimental studies have shown that the higher levels of ACE2 or increasing ACE2/ACE1 ratio improve COVID-19 outcomes through lowering inflammation and death. Aerobic moderate intensity physical exercise fights off infections by two mechanisms, the inhibition of ACE/Ang II/AT1-R pathway and the stimulation of ACE2/Ang-(1-7)/MasR axis. Exercise can also activate the anti-inflammatory response so that it can be a potential therapeutic strategy against COVID-19. Here, we summarize and focus the relation among COVID-19, RAS, and immune system and describe the potential effect of aerobic moderate intensity physical exercise against CoV as a useful complementary tool for providing immune protection against SARS-CoV-2 virus infection, which is a novel intervention that requires further investigation.

Caffeine co-ingested with carbohydrate on performance recovery in national-level paddlers: a randomized, double-blind, crossover, placebo-controlled trial

BACKGROUND

Caffeine enhances muscle glycogen re-synthesis post exercise; however, the next-day effects on recovery are unknown. The present study aimed to examine the effects of carbohydrate (CHO) supplementation with or without caffeine (CAF) 24-h following exhaustive exercise on time trial performance in elite paddling athletes.

METHODS

Nine highly trained male paddlers (21 ± 2 y) completed three experimental trials in a randomized, double-blind, crossover manner. Following an exhaustive exercise session (20-km timed paddle) participants ingested: (i) 0.6 g/kg of carbohydrate (CHO), (ii) 0.6 g/kg of carbohydrate with 6 mg/kg of caffeine (CAF+CHO), (iii) or placebo (PLA), at four time-points (immediately after, and 2, 6, and 12-h post-exercise) in addition to their typical dietary intake. After 24 h, 5 attempts of on-water 500-m paddling time-trial was performed, and the average time was recorded. Blood samples were taken at rest and following both the 20-km and the 5×500 m exercise to determine changes in plasma cortisol, insulin, and glucose.

RESULTS

There was a significant main effect of condition (P<0.001), with post hoc analysis revealing that both CHO conditions (CHO: 98.7 ± 2.8 s, P = 0.0003; CAF+CHO: 97.9 ± 2.3 s, P = 0.0002) were significantly faster compared to PLA (101.0 ± 3.1 s), however CAF did not augment time trial performance compared to CHO (P = 0.16). There was no significant condition by time interactions for glucose, cortisol, or insulin before and after the 20-km depleting exercise and 500-m time trial.

CONCLUSIONS

In elite male paddlers, CHO, independent of caffeine, enhanced time trial performance 24 hours following exhaustive exercise.

Influence of different training methods on cardiovascular disease risk markers after cessation of anabolic steroids abuse in bodybuilders at risk

Evidence suggests that anabolic-androgenic steroid (AAS) abuse induces adverse effects on cardiovascular disease (CVD). However, it is unclear whether different training methods are effective in reducing these consequences. This study aims to compare the effects of aerobic training (AT), resistance training (RT), and combined training (CT) on CVD risk markers in professional bodybuilders at risk after cessation of AAS abuse. Forty bodybuilders were randomly assigned to one of four groups: control (n=10), AT (n=10), RT (RT, n=10), and CT (n=10) groups. Before and after eight weeks of training, the high sensitivity C-reactive protein (hs-CRP), haematocrit (HCT), homocysteine (HCY), N-terminal prohormone of brain natriuretic peptide (NT-proBNP), and blood pressure (BP) were measured. Significant decreases within groups in HCY and CRP were observed (P<0.05). However, decreases were greater in training groups, and there was a significant difference between control and training groups (P<0.05). Increase in NT-proBNP, and decreases in systolic blood pressure (SBP), and diastolic blood pressure (DBP) levels were significant only in training groups (P<0.005). The increase of NT-proBNP was significant in the CT when compared to the RT (P<0.05). The present study found that discontinuing AAS consumption can improve some CVD risk markers in professional bodybuilders, but this effect could be improved if various modalities of training were performed. Accompanying AT with RT was also discovered to have a greater impact on some markers (including NT-proBNP).

Possible Effects of Beetroot Supplementation on Physical Performance Through Metabolic, Neuroendocrine, and Antioxidant Mechanisms: A Narrative Review of the Literature

Athletes often seek to use dietary supplements to increase performance during exercise. Among various supplements, much attention has been paid to beetroot in recent years. Beetroot is a source of carbohydrates, fiber, protein, minerals, and vitamins; also, it is a natural source of nitrate and associated with improved sports performance. Nitrates can the modification of skeletal muscle contractile proteins or calcium handling after translation. The time to reach the peak plasma nitrate is between 1 and 3 h after consumption of a single dose of nitrate. Nitrate is metabolized by conversion to nitrite and subsequently nitric oxide. Beetroot can have various effects on athletic performance through nitric oxide. Nitric oxide is an intracellular and extracellular messenger for regulating certain cellular functions and causes vasodilation of blood vessels and increases blood flow. Nitric oxide seems to be effective in improving athletic performance by increasing oxygen, glucose, and other nutrients for better muscle fueling. Nitric oxide plays the main role in anabolic hormones, modulates the release of several neurotransmitters and the major mediators of stress involved in the acute hypothalamic-pituitary-adrenal response to exercise. Beetroot is an important source of compounds such as ascorbic acid, carotenoids, phenolic acids, flavonoids, betaline, and highly active phenolics and has high antioxidant properties. Beetroot supplement provides an important source of dietary polyphenols and due to the many health benefits. Phytochemicals of Beetroot through signaling pathways inhibit inflammatory diseases. In this study, the mechanisms responsible for these effects were examined and the research in this regard was reviewed.

Effects of different resistance training frequencies on body composition and muscular performance adaptations in men

BACKGROUND

The aim of this study was to compare the effects of 8 weeks resistance training (RT) with two sessions versus four sessions per week under volume load-equated conditions on body composition, maximal strength, and explosive actions performance in recreationally trained men.

METHODS

Thirty-five healthy young men participated in the study and were randomly divided into a two sessions per-week RT (RT2, n = 12), four sessions per-week RT (RT4, n = 13) or a control group (CG, n = 10). All subjects were evaluated for thigh, chest and arm circumference, countermovement jump (CMJ), medicine ball throw (MBT), 1-repetition maximum (1RM) leg press, bench press, arm curl, muscular endurance (i.e., 60% of 1RM to failure) for leg press, and bench press at pre, mid (week 4) and post an 8-week training intervention.

RESULTS

A two-way analysis of variance with repeated measures (3 [group] × 3 [time]) revealed that both training groups increased chest and thigh circumferences, strength and explosive actions performance tests in comparison to CG following 8 weeks of training (p = 0.01 to 0.04). Group × time interactions were also noted in 1RM bench press (effects size [ES] = 1.07 vs. 0.89) and arm curl (ES = 1.15 vs. 0.89), with greater gains for RT4 than RT2 (p = 0.03).

CONCLUSION

RT improved muscle strength, explosive actions performance and markers of muscle size in recreationally trained men; however, four sessions of resistance training per week produced greater gains in muscular strength for the upper body measures (i.e., 1RM bench press and arm curl) when compared to two sessions per week under volume-equated conditions.

Comparison of traditional and accommodating resistance training with chains on muscular adaptations in young men

BACKGROUND

Providing accommodating resistance with the use of chains (CRT) is a programming technique that may enhance muscle size, strength, and power. However, there is a paucity of studies comparing the responses to CRT and traditional resistance training (TRT) approaches. This study aimed to examine the effects of 8 weeks of CRT and TRT on muscular adaptations in young recreationally-trained men.

METHODS

Thirty men (26 ± 4 y) volunteered to participate in the present study and were randomly assigned to either CRT (n = 10), TRT (n = 10), or a non-exercise control group (CG, n = 10). A resistancetraining program (3-4 sets, ~8-12 repetitions at 65-80% of 1RM) was performed three times a week for 8 weeks. Percentage body fat, arm and thigh circumferences, 1RM and endurance (number of repetitions to failure 60% of 1RM) strength tests in the back squat and bench press exercises, and vertical jump power were assessed before and after the intervention.

RESULTS

Following the intervention, both training groups demonstrated improvements in strength compared to CG, where greater gains were observed for CRT (e.g., bench press 1RM: CRT=28%; TRT=19% / back squat endurance: CRT=8%; TRT=2%).

CONCLUSIONS

The use of chains during resistance training may promote greater gains in strength in young men.

Does regular resistance exercise improve resting and intradialytic pain and haemodynamic measures in sedentary chronic haemodialysis women?

Pain is one of the major problems in haemodialysis patients. Regular resistance exercise (RE), as an effective lifestyle modification, may play a role in reducing pain through changes in blood pressure (BP). Therefore, we aimed to evaluate the effect of RE training on pain, BP, and heart rate. In a randomised controlled trial, eighteen sedentary women completed the study in RE (n=10) or control (n=8) groups. In the exercise group, the patients had a circuit RE program in non-dialysis days, two times a week, for six weeks. The RE protocol consisted of six exercises performing with 10 repetitions at 50-60% of 1-repetition maximum. Resting and intradialytic pain threshold (algometer using a 1 kg pressure load), BP, and heart rate were measured 48 h before and after the intervention. There were no significant differences from pre- to post-intervention, or between the groups regarding pain threshold, systolic and diastolic BP, and heart rate at rest and during the haemodialysis process (P>0.05). Although the 6-week low-intensity RE training in non-dialysis days was safe for chronic haemodialysis women, it could not change resting and intradialytic pain and hemodynamic measures.

Interaction effect of green tea consumption and resistance training on office and ambulatory cardiovascular parameters in women with high-normal/stage 1 hypertension

This study aimed to investigate the chronic effects of green tea (GT) extract and resistance training (RT) on ambulatory and office blood pressure (BP), heart rate (HR), and rate-pressure product (RPP) in a sample of Iranian women with high-normal/stage 1 hypertension. Forty-four middle-aged sedentary women participated in this randomized, double-blind, placebo-controlled study. They were randomly assigned to one of four groups: GT and RT (GR, n = 11), RT (n = 10), GT (n = 10), or control (n = 13). Three weeks of GT consumption were followed by six weeks of the interaction with RT. GR and RT groups performed two circuits of RT at %50 of 1RM two days per week. RT and control groups also received placebo (maltodextrin) with the same timing. The changes of each variable from baseline to post-intervention were compared between the groups using the ANOVA test, and effect size (ES) statistic was also calculated. In comparison with the control group, significant reductions were found for office systolic BP (SBP, 8%, ES = 1.22), and 24 h-SBP (5%, ES = 1.2) in the RT group. However, GR group showed significant decreases in office SBP (10.5%, ES = 1.45), mean BP (8%, ES = 1.11), RPP (13%, ES = 1.47), 24 h-SBP (5%, ES = 1.21), and 24 h-RPP (10%, ES = 1.15). The interaction of regular RT and GT consumption seems to induce more beneficial effects on some important parameters including MBP and RPP when compared to RT or GT alone.

Acute effects of strength and endurance exercise on serum BDNF and IGF-1 levels in older men

Background

Regarding an important effects of physical exercise on brain function in elders, the aim of this study was to examine the effects of strength and endurance exercise on brain neurobiological factors in older men.

Methods

Thirty older men volunteered to participate in this study and were randomly assigned to strength, endurance and control groups. The subjects in strength group performed two circuits of resistance exercise (6 exercises with 10 repetition of 65–70% of one repetition maximum), while endurance group performed 30 min running with 65–70% of maximal heart rate. Blood was obtained pre and post-exercise to determine changes in serum BDNF, IGF-1 and platelets.

Results

After exercise, both the strength and endurance groups showed significant increases in serum BDNF and IGF-1 concentrations and platelets at post-exercise and in comparison to control group (p < 0.05). In addition, no statistically significant differences were detected between the strength and endurance groups at post-exercise.

Conclusion

Our findings indicate that both the strength and endurance interventions are effective in elevating BDNF, IGF-1, and platelets, without significant differences between them.

The Assessment of Some Metabolic Markers by Combination of Ursolic Acid Supplementation and Resistance Training in Young Older Obese Women

BACKGROUND

In this study, we explored the impacts of moderate-to-high intensity resistance circuit training (MHRCT) and Ursolic acid (UA) supplementation to improve these pathological changes in young older obese women (women between the ages of 50 and 70).

METHODS

The study included twenty-five young older women (age > 50 years and ≤70 years) with stage I-II obesity (BMI ≥ 30 and <40 kg/m2), who received eight weeks placebo with MHRCT, and MHRCT with UA supplementation. UA or placebo orally was ingested as a capsule three times per day for eight weeks. The following parameters were evaluated post- and pre-intervention. Data were analyzed using ANOVA with repeated measures.

RESULTS

Interleukin-15 (IL-15), Interleukin-6 (IL-6), Insulin, and HOMA-IR decreased significantly in the placebo and UA groups versus control, but the UA group significantly decreased compared with the placebo (p<0.05). In turn, the Brain-Derived Neurotrophic Factor (BDNF) and Irisin levels showed a significant increase in the placebo and UA groups versus control. However, the BDNF in the UA group significantly increased compared with the placebo (p < 0.05).

CONCLUSION

We demonstrated that applying resistance training can reverse the pathological changes that may occur with aging and a sedentary lifestyle. Our results showed that UA could enhance the effects of this type of exercise. Therefore, a combination of the resistance training program and UA supplementation may be considered as a novel and influential intervention to metabolic derangements and may also decrease the burden associated with this condition.

Oxidative Stress and Inflammation Induced by Waterpipe Tobacco Smoking Despite Possible Protective Effects of Exercise Training: A Review of the Literature

The prevalence of waterpipe tobacco smoking (WTS), which is also known as ghalyan, shisha or hookah, is increasing rapidly around the world, especially among youth. Growing interest in this form of tobacco smoking can be traced, in part, to the use of flavored tobacco products, social acceptability as a safer option than cigarettes, and its consideration as a relaxation method or entertainment. However, there is a well-established association between WTS and oxidative stress that causes irreversible chronic pathological conditions such as cardiovascular and respiratory problems, as well as different types of cancers, and thus increases the risk of mortality. Clearly, induction of inflammation status through increased reactive oxygen species (ROS), which in turn leads to oxidative stress and harm to lipids, DNA, and proteins, is the most plausible mechanism to explain the potential harmful effects of WTS. Unlike WTS, well-designed exercise training programs increase ROS to the extent that it is beneficial to the body. In this study, we aimed to review available evidence on the impact of exercise training on oxidative stress and inflammation status. We also summarize the effect of acute and chronic WTS on different exercise capacities.

Acute Responses of Cardiac Biomarkers to Intermittent and Continuous Exercise Are Related to Age Difference but Not I/D Polymorphism in the ACE Gene

Purpose

The purpose of this study was to determine the (i) cardiac biomarker (cTnI and NT-proBNP) responses to moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) in the middle-aged and young groups, (ii) relationship of post-exercise cardiac biomarker release between these two age groups, and (iii) investigate whether insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene is associated with predisposition to cardiac damage after exercise in Iranian men.

Methods

We examined cTnI and NT-proBNP in 29 middle-aged (54.5 ± 4.6 years) and 28 young (22.7 ± 4.2 years) soccer players before and after HIIE and MICE running tests.

Results

The middle-aged soccer players had higher baseline cTnI (0.015 ± 0.007 ng/ml vs. 0.010 ± 0.006 ng/ml; P = 0.01) and NT-proBNP (30.7 ± 13.6 ng/L vs. 18.4 ± 8.3 ng/L; P < 0.001) values compared with the young group. The changes with exercise (ΔcTnI: 13 vs. 11 ng/ml and ΔNT-proBNP: 18 vs. 11 ng/L) were also higher in the middle-aged group. No subject exceeded the upper reference limit for cTnI and NT-proBNP. Considering three ACE genotypes, the mean cTnI and NT-proBNP values of middle-aged and young groups did not show any significant difference.

Conclusion

Marked differences in baseline and post-exercise cTnI and NT-proBNP values were observed, which were related to age differences but not to ACE genotypes.

Association Between the Acute to Chronic Workload Ratio and Injury Occurrence in Young Male Team Soccer Players: A Preliminary Study

This study aimed to investigate the relationship between the acute to chronic workload ratio (ACWR), based upon participant session rating of perceived exertion (sRPE), using two models [(1) rolling averages (ACWR_RA); and (2) exponentially weighted moving averages (ACWR_EWMA)] and the injury rate in young male team soccer players aged 17.1 ± 0.7 years during a competitive mesocycle. Twenty-two players were enrolled in this study and performed four training sessions per week with 2 days of recovery and 1 match day per week. During each training session and each weekly match, training time and sRPE were recorded. In addition, training impulse (TRIMP), monotony, and strain were subsequently calculated. The rate of injury was recorded for each soccer player over a period of 4 weeks (i.e., 28 days) using a daily questionnaire. The results showed that over the course of the study, the number of non-contact injuries was significantly higher than that for contact injuries (2.5 vs. 0.5, p = 0.01). There were also significant positive correlations between sRPE and training time (r = 0.411, p = 0.039), ACWR_RA (r = 0.47, p = 0.049), and ACWR_EWMA (r = 0.51, p = 0.038). In addition, small-to-medium correlations were detected between ACWR and non-contact injury occurrence (ACWR_RA, r = 0.31, p = 0.05; ACWR_EWMA, r = 0.53, p = 0.03). Explained variance (r²) for non-contact injury was significantly greater using the ACWR_EWMA model (ranging between 21 and 52%) compared with ACWR_RA (ranging between 17 and 39%). In conclusion, the results of this study showed that the ACWR_EWMA model is more sensitive than ACWR_RA to identify non-contact injury occurrence in male team soccer players during a short period in the competitive season.

Comparable endocrine and neuromuscular adaptations to variable vs. constant gravity-dependent resistance training among young women

Background

Variable resistance has been shown to induce greater total work and muscle activation when compared to constant resistance. However, little is known regarding the effects of chronic exposure to variable resistance training in comparison with constant resistance training. The aim of the present study was therefore to examine the effects of chain-loaded variable and constant gravity-dependent resistance training on resting hormonal and neuromuscular adaptations.

Methods

Young women were randomly assigned to variable resistance training (VRT; n = 12; age, 23.75 ± 3.64 years; and BMI, 26.80 ± 4.21 kg m⁻²), constant resistance training (CRT; n = 12; age, 23.58 ± 3.84 years; BMI, 25.25 ± 3.84 kg m⁻²), or control (Con; n = 12; age, 23.50 ± 2.93 years; BMI, 27.12 ± 12 kg m⁻²) groups. CRT performed 8-week total-body free-weight training three times per week with moderate-to-high intensity (65–80% 1RM; periodized). VRT was the same as CRT but included variable resistance via chains (15% of total load). Resting serum samples were taken before and after the 8-week intervention for GH, IGF-1, cortisol, myostatin, and follistatin analyses.

Results

Both VRT and CRT groups displayed moderate-to-large significant increases in GH (197.1%; ES = 0.78 vs. 229.9%; ES = 1.55), IGF-1 (82.3%; ES = 1.87 vs. 66%; ES = 1.66), and follistatin (58.8%; ES = 0.80 vs. 49.15%; ES = 0.80) and decreases in cortisol (− 19.9%; ES = − 1.34 vs. − 17.1%; ES = − 1.05) and myostatin (− 26.9%; ES = − 0.78 vs. − 23.2%; ES = − 0.82). Also, VRT and CRT resulted in large significant increases in bench press (30.54%; ES = 1.45 vs. 25.08%; ES = 1.12) and squat (30.63%; ES = 1.28 vs. 24.81%; ES = 1.21) strength, with no differences between groups.

Conclusions

Implementing chain-loaded VRT into a periodized resistance training program can be an effective alternative to constant loading during free-weight RT among untrained young women.

Changes in pain following an interaction period of resistance training and green tea extract consumption in sedentary hypertensive women: impact of blood pressure swings

BACKGROUND

Changes in blood pressure (BP) may affect pain. However, the interaction effect of resistance training and green tea on BP and pain has not been studied. The primary aim of this study was to evaluate the impact of resistance training and green tea extract (GTE) on pain variables in hypertensive patients. Secondary aim included determining the effects of BP alterations on pain responses.

METHODS

In a randomized, double-blind, placebo-controlled study, 30 middle-aged sedentary women were randomly divided into resistance training and green tea extract (GR, n = 8), resistance training (R, n = 8), green tea (G, n = 7), and control groups (C, n = 7). The study period consisted of 3 weeks of GTE (~ 245 mg total polyphenols) consumption twice a day followed by 6 weeks of interaction with resistance training. GR and R groups performed two circuits of training with ten repetitions at 50% of 1RM 2 days a week while other two groups had no any regular exercise training. R and C groups also received placebo capsules (maltodextrin) with the same timing. Pain threshold and perception, BP, and heart rate were recorded following the first and last session of training at rest and 5th and 15th minute.

RESULTS

Pain perception of training groups after the last session was significantly higher than control conditions, and at this time, the magnitude of BP responses was lower in training groups. In proportion to pain threshold, there were no significant differences between groups.

CONCLUSION

It seems that training-induced hypotension can alter pain perception in hypertensive women through changes in baroreceptor activation.

Salivary Antioxidants Status Following Progressive Aerobic Exercise: What Are the Differences between Waterpipe Smokers and Non-Smokers?

Waterpipe tobacco (WPT) smoking is a public health problem with similar or even stronger effects than cigarette smoking. Although it appears to be associated with extensive oxidative stress, there is a limited number of studies on the oxidative effects of WPT smoking in stressful conditions. We, therefore, compared the responses of salivary flow rate (SFR), uric acid (UA) concentration, and peroxidase (POX) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) activities between WPT smokers and non-smokers following a bout of exhaustive aerobic exercise (AE). Twenty-three sedentary young women (age: 22.95 ± 2.83 years) participated in this study, including 11 smokers (7.00 ± 1.41 uses/week) and 12 non-smokers. All participants were required to perform the Bruce protocol treadmill test at an initial gradient of 10% at 1.7 mph, with increases of these parameters every 3 min until exhaustion. Unstimulated saliva samples were collected before, immediately after, and 1 hour after AE. WPT smokers showed lower SFR compared with non-smokers at all time points (p < 0.05). In comparison to WPT smokers, a larger increase in POX activity (approximately 23% vs. 14%; p = 0.009) and a smaller decline in DPPH activity (approximately -8% vs. -15%; p = 0.004) were found in non-smokers compared with WPT smokers. While these changes were slowly compensated within 1 hour after exhaustion, the activity of both markers was different from the pre-exercise values (p < 0.001). There was also a trend for UA concentration in non-smokers to be higher during the recovery period, with no significant difference between the groups (p > 0.05). It seems that WPT smoking is associated with negative effects on important human antioxidants and a diminished antioxidative response following acute exercise.

In-season in-field variable resistance training: effects on strength, power, and anthropometry of junior soccer players

BACKGROUND

Soccer players' leg muscular strength and power have been shown to be significant due to their association with soccer-specific performance including jumps, sprints, tackles and kicks. The aim of this study, therefore, was to examine the effects of an in-season in-field variable resistance training (VRT) program on strength, power, and anthropometry of junior soccer players.

METHODS

A team of male soccer players were randomly assigned into Experimental (N.=10) and Control groups (N.=10). The Control group performed 8 weeks of soccer training alone. The Experimental group performed squat VRT using chains in addition to soccer training. Measures before and after training included squat strength, countermovement jump, and anthropometric estimation of thigh muscle cross sectional area (CSA).

RESULTS

The VRT induced large improvements in absolute (34.45%; P=0.001; Cohen's d=1.78) and relative strength to thigh muscle CSA (21.53%; P=0.002; Cohen's d=1.04). Similarly, there were large (18.07%, P=0.007; Cohen's d=1.5) increases in jump height and medium gains in absolute peak power output (16.13%; P=0.009; Cohen's d=0.34) and relative peak power output to thigh muscle CSA (9.6%; P=0.002; Cohen's d=0.31). Further, there was a medium increase (5.9%, P=0.03; Cohen's d=0.36) in thigh muscle CSA. No significant changes were observed in the Control group.

CONCLUSIONS

In-season in-field biweekly squat VRT enhanced strength and power measures in junior soccer players.

β-Hydroxy-β-Methylbutyrate Free Acid Attenuates Oxidative Stress Induced by a Single Bout of Plyometric Exercise

PURPOSE

The purpose of this study was to examine the effect of β-hydroxy-β methylbutyrate free acid (HMB-FA) ingestion on oxidative stress and leukocyte responses to plyometric exercise.

METHODS

In a randomized double-blind placebo-controlled design, physically active males were assigned to the HMB-FA (n = 8) or placebo (n = 8) groups that consumed either 1 g of HMB-FA or placebo 30 min prior to performing an acute plyometric exercise protocol (15 sets of 10 repetitions of maximal-effort vertical jumps). Blood was obtained pre-(T1), post-(T2), and 1-h post-(T3) exercise to determine changes in serum levels of 8-hydroxy-2-deoxyguanosine (8-OHdG), malondialdehyde (MDA), protein carbonyl (PC), and white blood cells (WBC).

RESULTS

The exercise protocol significantly elevated 8-OHdG (HMB-FA, T2 9.5 and T3 12.6%; placebo, T2 18.2 and T3 36.5%), MDA (HMB-FA, T2 11.6 and T3 25.2%; placebo, T2 11.8 and T3 41%) and PC (HMB-FA, T2 6.9 and T3 25%; placebo, T2 23.4 and T3 55.3%) at post- and 1-h post-exercise, respectively. However, at 1-h post-exercise, greater increases in oxidative stress markers (8-OHdG 36.5 vs. 12.6%; MDA 41 vs. 25.1% and PC 55.3 vs. 25%) were observed in the placebo group compared to the HMB-FA group (p < 0.05). In addition, the WBC level was greater for the placebo group in comparison to the HMB-FA group at post-exercise.

CONCLUSION

HMB-FA attenuated oxidative stress and leukocyte responses to plyometric exercise compared with placebo.

Acute Effects of Mental Activity on Response of Serum BDNF and IGF-1 Levels in Elite and Novice Chess Players

Background and Objectives: Although the effects of physical exercise on brain functions are well studied, the influence of mental activity is unknown. The aim of this study was to assess the influence of a session of mental activity on brain neurobiological factors in chess players. Materials and Methods: Ten elite and novice chess players were recruited to participate in this study as volunteers. The subjects performed a session of standard chess matches as a mental activity. Before and after each chess match, blood samples were drawn to analyze changes in serum brain-derived neurotrophic factor (BDNF) and insulin-like growth factor 1 (IGF-1). Results: After each chess match, both the elite and novice groups showed significant increases in serum BDNF and IGF-1 concentrations. The elite group also showed significantly greater changes in BDNF and IGF-1 levels (p ≤ 0.05) than the novice group. Conclusions: Our findings indicate that a session of standard chess matches as a mental activity is effective for elevating BDNF and IGF-1 levels, and that their elevation in elite players seems to be more pronounced than those in novice players.

Association of ACE gene polymorphism with cardiovascular determinants of trained and untrained Iranian men

Background

The insertion (I) rather than deletion (D) of human angiotensin converting enzyme gene (ACE) is associated with lower circulating ACE activity and with endurance performance among Caucasians. The frequency of the ACE gene I/D allele in Iranian sample seems to be more similar to the Caucasians. To assess the possible relationship between I/D polymorphism of ACE gene with athletic status and selected cardiovascular indices and VO_2max in an Iranian population, DNA samples were obtained from 57 trained and untrained men, with soccer as their main training modality. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. VO_2max was determined by an incremental test to volitional exhaustion on a motorized treadmill.

Results

I/D genotype was neither associated with elite athlete status nor with VO_2max, resting heart rate, systolic and diastolic blood pressure. There was no interaction effect of training statue x ACE genotype for each of the examined indices.

Conclusions

ACE gene variation was not a determinant of cardiovascular function and VO_2max in either trained or untrained Iranian participating in soccer. The absence of an association between either I/D genotype and elite Iranian athlete status and better cardiovascular function also suggests that the ACE gene does not contribute significantly to the phenomenal success of Iranian soccer players.

Effects of aerobic versus resistance training on serum fetuin-A, fetuin-B, and fibroblast growth factor-21 levels in male diabetic patients

The aim of this study was to compare the effects of 8 weeks of aerobic versus resistance training programs on serum fetuin-A, fetuin-B, and fibroblast growth factor-21 (FGF-21) levels in males with type 2 diabetes mellitus. Participants (n = 34) were randomly assigned to a resistance training group (RTG; n = 12), an aerobic training group (ATG; n = 11), or a control group (n = 11). The ATG completed 30-45 min of aerobic running training at 65%-75% of the maximum heart rate. The RTG completed three sets of 10 repetitions maximum of leg press, bench press, knee extension, seated cable row, knee flexion, military press, and calf rise. Blood samples were taken before and after the training period to assess dependent variables. After 8 weeks, both the ATG and the RTG reduced fetuin-A (p < 0.05) and fetuin-B (p < 0.05), but increased FGF-21 (p < 0.05). Moreover, the RTG showed greater decrease than the ATG in fetuin-A (-18.3% vs. -7.9%), fetuin-B (-29.2% vs. -11.45%), and a lower increase in FGF-21 (42.2% vs. 25.1%), respectively. Aerobic and resistance exercise training significantly decreased serum fetuin-A, and fetuin-B, and increased FGF-21 levels in males with type 2 diabetes mellitus. However, more significant alterations in serum factors were observed from resistance training. Thus, resistance training may be considered a more suitable training strategy.

25-Hydroxyvitamin D levels and its relation to muscle strength, maximal oxygen consumption, and body mass index in young and middle adulthood women

Introduction

Vitamin D is a potent secosteroid hormone that provides many health benefits. The ubiquitous nature of vitamin D receptor (VDR) suggests widespread effect.

Purpose

The purpose of this study was to investigate the relationship between 25-hydroxyvitamin D (25OHD) levels and muscle strength, maximal oxygen consumption (VO₂max), and body mass index (BMI) in Iranian young and middle adulthood women.

Participants and methods

A cross-sectional descriptive study was conducted in 182 healthy Iranian women within the age range of 26–60 years. Body weight and height were measured, and BMI was calculated. VO₂max was determined by the Rockport test. Muscle strength was determined by the chest press, leg press, and hand grip test. Also, circulating levels of 25OHD were evaluated.

Results

Results showed a significant relationship between 25OHD levels and BMI, VO₂max, and muscle strength (chest press, leg press, hand grip dominant hand [HGDH], and hand grip nondominant hand [HGNDH]) in young and middle adulthood women (BMI in young and middle adulthood: r=−0.48, P<0.001 and r=−0.27, P=0.01, respectively; VO₂max in young and middle adulthood women: r=0.69, P<0.001 and r=0.57, P<0.001, respectively; chest press, leg press, HGDH, and HGNDH in young adulthood: r=0.58, r=0.59, r=0.65, and r=0.42, respectively, P<0.001; and in middle adulthood: r=0.73, r=0.34, r=0.66, and r=0.55, respectively, P≤0.001). Multiple linear regression analysis showed that higher levels of VO₂max, HGDH, and chest press predicted higher 25OHD levels in the young adulthood women (R²=0.75; β=0.39, β=0.35, and β=0.30, respectively; P<0.001). Moreover, VO₂max and HGDH were the strongest predictor of 25OHD levels in the middle adulthood women (R²=0.71; β=0.35, β=0.40, respectively; P<0.001).

Conclusion

Based on the results, it could be concluded that VO₂max and strength are useful indirect marker for 25OHD levels in the young and middle adulthood women. It also seems that VO₂max and HGDH strength had stronger associations with 25OHD levels in the young adulthood women, and chest press and HGDH had stronger associations with 25OHD levels in the middle adulthood women.

The relationship between second-to-fourth digit ratio (2D:4D), muscle strength and body composition to bone mineral density in young women

2D:4D ratio is determined by balance between androgens and estrogens. Low level estrogen reduces bone mineral density (BMD) and incurs negative changes to bone microarchitecture, increasing the risk of osteoporosis and, as a consequence, fracture risk in women. The purpose of this study was to investigate the relationship between 2D:4D, muscle strength and body composition to BMD in young women. One hundred twenty-seven young women (age range 24-36 years) voluntarily participated in this study. Lengths of the second (index) and fourth (ring) fingers, upper and lower body strength and body composition (body mass index, BMI; waist to hip ratio, WHR) and body fat percentage were estimated. Also, blood levels of calcium and 25-hydroxyvitamin D (25OHD) were evaluated and dual-energy X-ray absorptiometry device was used to measure BMD in the lumbar spine (LS) and femoral neck (FN). The results showed that digit ratios, upper body and lower body muscle strength, BMI and fat percentage had a positive relationship with LS and FN BMD (LS BMD: r=.47, r=.56, r=.46, r=.34, r=.28, p≤.001, respectively; FN BMD: r=.34, r=.49, r=.51, r=.45, r=.27, p≤.001, respectively). In addition, there was no significant relationship between WHR and BMD of LS and FN (p˃.05). Multiple linear regression analysis showed the upper body strength was a stronger determinant of LS BMD and the lower body strength was a stronger determinant of FN BMD. Based on the results, the researchers concluded that upper and lower body strength, 2D:4D ratios and BMI were important determinants of young women’s BMD. Also, it seemed that some of these factors may be able to help predicting the osteoporosis potential in young women

Practical Model of Low-Volume Paddling-Based Sprint Interval Training Improves Aerobic and Anaerobic Performances in Professional Female Canoe Polo Athletes

Sheykhlouvand, M, Khalili, E, Gharaat, M, Arazi, H, Khalafi, M, and Tarverdizadeh, B. Practical model of low-volume paddling-based sprint interval training improves aerobic and anaerobic performances in professional female canoe polo athletes. J Strength Cond Res 32(8): 2375-2382, 2018-Brief, intense exercise training using running and cycling as exercise interventions may induce aerobic and anaerobic adaptations in athletes from a wide range of sports. However, this has not been studied extensively for those sports in which the upper body is predominantly involved. Our purpose was to examine the effects of kayak paddling-based sprint interval training (SIT) on cardiorespiratory fitness and anaerobic performance. Sixteen professional female canoe polo athletes (age = 27.6 ± 1.9 years; height = 165.7 ± 5.2 cm; body mass = 62.6 ± 8.5 kg; body mass index = 22.8 kg·m; body fat = 23.8 ± 4.9%) were randomized to either an intense exercise training consisting of sets of 5 × 5-second maximum sprint efforts interspersed by a 10-second recovery between each sprint (3, 4, 5, and 6 sets/session from first to fourth week, respectively, with 3 minutes of rest between each set), performed 3 times per week for 4 weeks (n = 8), or a usual training control group (n = 8). Before and after the training period, aerobic and anaerobic measurements were assessed using a kayak specific test and Wingate protocol, respectively. Training increased V[Combining Dot Above]O2peak, O2 pulse, anaerobic threshold, peak, and mean power output in the SIT group compared with the control group (p ≤ 0.05) who showed no changes in these variables when tested 4 weeks apart without SIT. Paddling-based SIT was a potent stimulus and time-efficient strategy to induce rapid adaptations in aerobic and anaerobic performances in professional female canoe polo athletes who can use this training method to achieve fitness in a short period.

A Review of the Effects of Leucine Metabolite (β-Hydroxy-β-methylbutyrate) Supplementation and Resistance Training on Inflammatory Markers: A New Approach to Oxidative Stress and Cardiovascular Risk Factors

β-hydroxy β-methylbutyrate (HMB) is a bioactive metabolite formed from the breakdown of the branched-chain amino acid, leucine. Given the popularity of HMB supplements among different athletes, specifically, those who participate in regular resistance training, this review was performed to summarize current literature on some aspects of HMB supplementation that have received less attention. Because of the small number of published studies, it has not been possible to conclude the exact effects of HMB on cardiovascular parameters, oxidative stress, and inflammatory markers. Thus, the interpretation of outcomes should be taken cautiously. However, the data presented here suggest that acute HMB supplementation may attenuate the pro-inflammatory response following an intense bout of resistance exercise in athletes. Also, the available findings collectively indicate that chronic HMB consumption with resistance training does not improve cardiovascular risk factors and oxidative stress markers greater than resistance training alone. Taken together, there is clearly a need for further well-designed, long-term studies to support these findings and determine whether HMB supplementation affects the adaptations induced by resistance training associated with the body’s inflammatory condition, antioxidative defense system, and cardiovascular risk factors in humans.

Low-Volume High-Intensity Interval Versus Continuous Endurance Training: Effects on Hematological and Cardiorespiratory System Adaptations in Professional Canoe Polo Athletes

Sheykhlouvand, M, Gharaat, M, Khalili, E, Agha-Alinejad, H, Rahmaninia, F, and Arazi, H. Low-volume high-intensity interval versus continuous endurance training: effects on hematological and cardiorespiratory system adaptations in professional canoe polo athletes. J Strength Cond Res 32(7): 1852-1860, 2018-The aim of this study was to compare the effect of 2 paddling-based high-intensity interval training (HIIT) and continuous endurance training (CET) on hematological, immunological, and cardiorespiratory adaptations in professional canoe polo athletes. A total of 21 male canoe polo athletes were randomly divided into 1 of 3 groups (N = 7): (a) HIIT with variable intensity (VIHIIT) (6 × 60 seconds at 100, 110, 120, 130, 130, 130, 120, 110, 100% vV[Combining Dot Above]O2peak from first to ninth session, respectively, 1:3 work to recovery ratio); (b) HIIT with variable volume (VVHIIT) (6, 7, 8, 9, 9, 9, 8, 7, 6 repetitions/session from first to ninth session, respectively) × 60 seconds at lowest velocity that elicited V[Combining Dot Above]O2peak (vV[Combining Dot Above]O2peak), 1:3 work to recovery ratio); and (c) the CET group performed 3 times × 60 minutes paddling sessions (75% vV[Combining Dot Above]O2peak) per week for 3 weeks. Significant increases in V[Combining Dot Above]O2peak (ml·kg·min) (VIHIIT = 7.6%, VVHIIT = 6.7%), ventilation (V[Combining Dot Above]E) at V[Combining Dot Above]O2peak (VIHIIT = 11.5%, VVHIIT = 15.2%), respiratory frequency (Rf) at V[Combining Dot Above]O2peak (VVHIIT = 21.1%), V[Combining Dot Above]O2 at ventilatory threshold (VT) (VIHIIT = 10.5%, VVHIIT = 25.1%), V[Combining Dot Above]E at VT (VIHIIT = 12.4%, VVHIIT = 34.0%), tidal volume at VT (VIHIIT = 11.7%, VVHIIT = 33.3%), Rf at VT (VIHIIT = 9.7%), V[Combining Dot Above]E/V[Combining Dot Above]O2 at VT (VVHIIT = 13.1%), V[Combining Dot Above]O2/heart rate (HR) at VT (VIHIIT = 12.9%, VVHIIT = 21.4%), and V[Combining Dot Above]E/HR at VT (VIHIIT = 7.8%, VVHIIT = 27.2%) were seen compared with pretraining. Training interventions resulted in significant increases in mean platelet volume (VIHIIT = 2.7%, VVHIIT = 1.9%), mean corpuscular hemoglobin concentration (CET = 3.3%), and significant decrease in red blood cell distribution width (VVHIIT = -4.3), and cell numbers of lymphocyte (CET = -27.1) compared with pretraining. This study demonstrated that paddling-based HIIT enhances aerobic capacity and respiratory makers, without negatively affecting the immune system over 3 weeks.

The Effects of Beta-Hydroxy-Beta-Methylbutyrate-Free Acid Supplementation and Resistance Training on Oxidative Stress Markers: A Randomized, Double-Blind, Placebo-Controlled Study

The aim of this study was to investigate the effects of 6-week beta-hydroxy-beta methylbutyrate-free acid (HMB-FA) supplementation on oxidative stress and biochemical variables in responses to resistance training. Sixteen healthy young males participated in this study and were randomly assigned to a HMB-FA supplementation group (n = 8) or a placebo supplementation group (n = 8). The resistance training program was applied for 6 weeks with two sessions per week. Blood samples were collected before and after training, and 8-hydroxy-2-deoxyguanosine (8-OHdG), malondialdehyde (MDA), protein carbonyl (PC), and biochemical variables, such as alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and the numbers of total white blood cells (WBC), neutrophils, lymphocytes, and monocytes were analyzed. Following intervention, both the HMB-FA and placebo supplementation groups showed significant decreases in MDA (effect size [ES]; &minus;0.39, &minus;0.33) and PC (ES; &minus;1.37, &minus;1.41), respectively. However, 8-OHdG did not change after 6 weeks of training in any of the groups. In addition, both groups showed similar training effects on biochemical variables after 6 weeks of intervention. It was concluded that HMB-FA supplementation during resistance training did not add further adaptive changes related to oxidative stress markers.

The effects of maturation on jumping ability and sprint adaptations to plyometric training in youth soccer players

The aim of this study was to investigate the effects of maturation on power and sprint performance adaptations following 6 weeks of plyometric training in youth soccer players during pre-season. Sixty male soccer players were categorized into 3 maturity groups (Pre, Mid and Post peak height velocity [PHV]) and then randomly assigned to plyometric group and control group. Vertical jump, standing long jump, and 20-m sprint (with and without ball) tests were collected before- and after-intervention. After the intervention, the Pre, Mid and Post-PHV groups showed significant (P ≤ 0.05) and small to moderate effect size (ES) improvement in vertical jump (ES = 0.48; 0.57; 0.73), peak power output (E = 0.60; 0.64; 0.76), standing long jump (ES = 0.62; 0.65; 0.7), 20-m sprint (ES = -0.58; -0.66), and 20-m sprint with ball (ES = -0.44; -0.8; -0.55) performances. The Post-PHV soccer players indicated greater gains than Pre-PHV in vertical jump and sprint performance after training (P ≤ 0.05). Short-term plyometric training had positive effects on sprinting and jumping-power which are important determinants of match-winning actions in soccer. These results indicate that a sixty foot contact, twice per week program, seems effective in improving power and sprint performance in youth soccer players.

Profiling and predicting performance of indoor rock climbers

The aim of this study is to establish somatotype and profile the anthropometric and biomotor characteristics of indoor rock climbers. Fourteen elite level male and ten recreational female Iranian indoor rock climbers completed a battery of tests. All anthropometric measurements were performed according to the recommendations of international standards for anthropometric assessment. Upper body strength and endurance were assessed by isometric tests. Explosive power and balance were also evaluated by Sargent jump and Star Excursion Balance Test (SEBT), respectively. Samples’ somatotypes were calculated by the method of Heath and Carter. Pearson’s correlation coefficient and partial correlations were calculated and stepwise multiple regression analyses were implemented to determine a set of best predictors of elite male climbers’ ability. Shoulder width, body fat content, upper-body strength and endurance for females, showed the most correlation with the climbing ability (range: r = 0.46–0.7, p ≤ 0.05), while among the male samples, these correlations with the climbing ability were mostly between WHR, absolute and relative to body mass handgrip strength, SEBT performance and the left-hand digit ratio. The results of stepwise multiple regression revealed that the SEBT performance in the posterior direction of right foot stance and Upper Extremity Girth Index are able to explain 62% of the variance of climbing ability. It is likely that decreasing the fat mass has no direct impact on the climbers’ performance. Also, SEBT performance is able to predict 35% of climbing performance. Hence, it seems balance exercises could be effective in improvement of climbing performance. 

The effects of Panax ginseng supplementation on growth hormone, cortisol and lactate response to high-intensity resistance exercise

Study aim: Growth hormone, cortisol, and lactate play an effective role in regulating and stimulating the muscle building proc­ess. The current study aimed to investigate the impact of Panax ginseng supplementation on growth hormone, cortisol, and lactate response to intense resistance exercise in young female non-athletes. Materials and methods: Ten non-athlete girls participated in this double-blind counter-balanced crossover study. They were assigned to two groups: the ginseng group and the placebo group. In two 4-week periods, they received the supplement and the placebo. In the first four weeks, 5 participants received ginseng (100 mg daily) and 5 others received placebo (maltodextrin). At the end of the 4 weeks, blood samples (5 ml) were taken to measure blood levels of the factors. Afterwards, the resistance exercise protocol was implemented, and immediately after that blood samples were taken. In the second four-week period, the five participants who had taken ginseng received placebo, and the five subjects who had received placebo took ginseng. The same tests were administered again. Results: The results showed that except for cortisol in the ginseng group, there were significant pre - to post-exercise changes for all 3 indicators in both groups. No significant difference was observed in pre - to post-exercise changes in the levels of GH (p = 0.71), cortisol (p = 0.34), or lactate (p = 0.90) between groups. Conclusions: 100 mg ginseng consumption daily for 4 weeks does not have an impact on the response of GH, cortisol, or lac­tate to high-intensity resistance exercise in young female non-athletes.

The interaction effects of resistance training and sustanon abuse on liver antioxidant activities and serum enzymes in male rats

BACKGROUND

Anabolic-androgenic steroids (AAS) are synthetic drugs derived from testosterone, the uncontrolled usage of which may lead to serious side effects. Previous studies have shown that resistance training (RT) is the main exercise modality practiced by AAS abusers. Thus, this work was carried out to evaluate the hepatotoxic effects of sustanon (Su) as an example of AAS in trained male rats.

METHODS

Rats were divided into sedentary/non-Su, sedentary/Su, RT/non-Su, and RT/Su. Su-administration groups received Su 10 mg/kg intramuscularly once a week for 8 weeks. In the 8-week RT, the rats climbed a vertical ladder 3 days/week.

RESULTS

After Su administration, the mean values of serum parameters related to hepatic function were within normal ranges. Superoxide dismutase, glutathione peroxidase, and glutathione reductase activities were higher (P < 0.05) in the liver of Su-treated rats. Chronic exercise alone did not change any of the above parameters.

CONCLUSIONS

The present findings suggest that the 8-week injection of Su, either with or without concurrent RT upregulation of enzymatic antioxidant activities and RT, did not attenuate the increase of enzymatic activities due to the Su administration. Furthermore, Su abuse in this dose did not make any severe liver damage.

The effect of resistance training set configuration on strength, power, and hormonal adaptation in female volleyball players

The primary purpose of this investigation was to determine the impact of altering the set structure during an 8-week resistance training program on anthropometric, hormonal, and strength power characteristics. Thirty female volleyball players were recruited for participation and then randomly assigned to 1 of 3 resistance training groups: (i) cluster sets (CRT; n = 10), (ii) traditional sets (TRT; n = 10), or (iii) control (CON; n = 10). All athletes were evaluated for thigh and arm circumference, vertical jump, 20-m sprint, 4 × 9-m shuttle-run, 1-repetition maximum (1RM) back squat, bench press, military press, and deadlift prior to and after an 8-week periodized training intervention. Blood samples were taken before and after the 8-week training period to evaluate resting testosterone, cortisol, and insulin-like growth factor 1 responses to the training period. After 8 weeks of training the CRT group displayed a small but significant improvement in vertical jump (CRT: effect size (ES) = 038, 7.1%) performance when compared with the TRT group (ES = 0.34, 5.6%). Both the CRT and TRT training interventions resulted in very large increases in the 1RM squat (CRT: 8.4% ± 1.2%; TRT: 7.3% ± 0.6%), bench press (CRT: 8.3% ± 2.0%; TRT: 8.7% ± 1.9%), military press (CRT: 5.7% ± 1.2%; TRT: 5.5% ± 1.6%), and deadlift (CRT: 8.2% ± 1.6%; TRT: 8.3% ± 2.2%). There were no significant differences in 20-m sprint or 4 × 9-m shuttle run times between the CRT, TRT, and CON groups. These results suggest that cluster sets allow for greater improvements in vertical jump performance and equal improvements in strength gains to those seen with traditional sets.

Physical and physiological profile of Iranian world-class karate athletes

Study aim: The purpose of the present research was to determine the physical and physiological features of international level karate athletes. Material and methods: Eleven male karate athletes who were ranked at the top of their weight categories participated in this study. All of them were evaluated for anthropometric, body composition, somatotype and bio-motor characteristics in detail. Results: The main results (mean ± SD) were height: 181.54 ± 4.71 cm; sitting height: 97.27 ± 3.03 cm; arm span: 185.72 ± 7.28 cm; BMI: 25.02 ± 3.32 kg ∙ m-2; Rohrer’s index: 137.68 ± 16.72; skelic index: 53.58 ± 1.29; arm span (ape) index: 1.02 ± 0.02; fat mass: 7.51 ± 4.56 kg; fat-free mass: 75.26 ± 10.04 kg; body fat: 8.66 ± 3.65; endomorphy: 2.4 ± 0.85; mesomorphy: 5.2 ± 1.13; ectomorphy: 2.11 ± 0.99; VO2max: 51.58 ± 3.39 ml ∙ kg-1 ∙ min-1; anaerobic power: 45.45 ± 4.39 W ∙ kg-1; long jump: 249.7 ± 16.81 cm; upper-body strength: 100.27 ± 15.61 kg (1.21 ± 0.07 kg ∙ kg-1); lower-body strength: 155.94 ± 19.49 kg (1.89 ± 0.14 kg ∙ kg-1); whole-body strength: 156.97 ± 21.38 kg (1.9 ± 0.13 kg ∙ kg-1) and flexibility: 37.63 ± 10.73 cm. Conclusions: A tall stature and long arm span, low body fat, markedly high mesomorphic build, moderately high aerobic power, outstanding anaerobic power, excellent lower-body explosive power, great muscular strength and high flexibility seem to be advantageous features for karate contestants.