Moderate-Intensity Continuous Training or High-Intensity Interval Training with or without Resistance Training for Altering Body Composition in Postmenopausal Women

Effects of a 6-Week Concurrent Training Program Combining Resistance and Various Modalities of Aerobic Exercise in Obese Women with Prehypertension: A Randomized Controlled Trial

Background/Objectives: Our study aimed to verify the effects of 6 weeks of concurrent training composed of resistance training (RT) and different modalities of aerobic exercise (moderate-intensity continuous training (MICT) or high-intensity interval training (HIIT)) on body composition, blood pressure, vascular function, autonomic nervous system (ANS) function, blood lipid levels, cardiometabolic index (CMI), and health-related fitness in obese middle-aged women with prehypertension. Methods: We selected 26 middle-aged women with obesity and prehypertension and divided them equally into the RT + MICT (n = 13) and RT + HIIT (n = 13) groups. The concurrent training program consisted of warm-up, RT, aerobic exercise (MICT or HIIT), and cool-down, and was performed for 6 weeks, three times a week, 85-100 min per session. The measured dependent parameters were analyzed before and after training. Results: Concurrent training (RT + MICT and RT + HIIT) for 6 weeks showed significant improvements in body composition, blood pressure, vascular function, ANS function, CMI, and health-related fitness. However, the RT + HIIT group showed a relatively greater improvement in blood lipid levels compared to the RT + MICT group. Conclusions: Our study confirmed that both RT + MICT and RT + HIIT yielded similar positive effects on most health-related parameters in obese middle-aged women with prehypertension. Among them, RT + HIIT appeared to be relatively more effective in improving blood lipid profiles.

Effects of 10 weeks of walking-based exercise training on resting substrate oxidation in postmenopausal women with obesity

BACKGROUND AND AIMS

Accumulating evidence supports the effectiveness of moderate-intensity aerobic training on metabolic health, with limited studies investigating change in resting substrate oxidation. The aim of this study was to explore whether 10 weeks of walking-based aerobic training would alter substrate oxidation in postmenopausal women with obesity.

METHODS AND RESULTS

Twenty-four postmenopausal women with obesity who were assigned into the control (n = 12) or exercise groups (n = 12) undertook a 10-week aerobic training program (3 d·week-1) that involved walking exercises at 50-70% of heart rate reserve on a treadmill, with exercise volume increased from 25 to 40 min·day-1. Resting metabolic rate (RMR) and body composition were measured pre- and post-training. Whole-body substrate oxidation was calculated using respiratory data collected during RMR measurement via indirect calorimetry. No significant change was noted (p > 0.05) in resting fat oxidation and carbohydrate oxidation in the exercise group. Resting respiratory exchange ratio and RMR did not alter in response to the training program (p > 0.05).

CONCLUSION

Our results show that a 10-week of moderate-intensity aerobic training does not modify substrate oxidation in postmenopausal women with obesity.

The hypothalamic estrogen receptor α pathway is involved in high-intensity interval training-induced visceral fat loss in premenopausal rats

BACKGROUND

Visceral adipose tissue (VAT) is strongly associated with metabolic diseases. Both high-intensity interval training (HIT) and moderate-intensity training (MIT) reduce VAT effectively; however, HIT might mediate greater VAT loss in females. The estrogen receptor α (ERα) pathway may play a key role. The aim of the present study was to confirm the role of adipose/hypothalamic ERα in HIT/MIT-mediated VAT loss, as well as the associated hypothalamic electrophysiology and body catabolism changes in pre- and post-menopausal animal models.

METHODS

Ovariectomy (OVX) or sham surgeries were conducted to establish pre/postmenopausal female rat models. After distance-matched long-term HIT and MIT interventions, ERα expression in hypothalamic/VAT, as well as food intake, spontaneous physical activity (SPA), VAT mass and morphology, local field potential (LFPs) in paraventricular nuclei (PVN) and excessive post-exercise oxygen consumption (EPOC), were observed. A target chemical block during the post-exercise recovery period was executed to further verify the role of the hypothalamic ERα pathway.

RESULTS

HIT enhanced the expression of ERα in the hypothalamus rather than VAT in the pre-, but not the postmenopausal group, which was accompanied by elevated LFP power density in α and β bands, enhanced EPOC and larger VAT loss than MIT. Chemical blockade of ERα suppressed EPOC and VAT catabolism mediated by HIT.

CONCLUSION

During the post-exercise recovery period, the hypothalamic ERα pathway involved in HIT induced EPOC elevation and VAT reduction in premenopausal female rats.

Low creatinine to cystatin C ratio is associated with lower muscle volumes and poorer gait speeds in the longitudinal Integrated Women's Health Program cohort

OBJECTIVE

Little is known about the longitudinal associations between creatinine-cystatin C ratios (CCR) with muscle volume and function during the menopausal transition. We investigated the longitudinal relationship of baseline CCR, with muscle volumes measured by magnetic resonance imaging (MRI), and objectively measured muscle strength and physical performance after 6.6-year follow-up.

METHODS

Participants from the Integrated Women's Health Programme (IWHP) cohort (n = 891, baseline mean age 56.2 ± 6.0) who attended both baseline and follow-up visits underwent objectively measured muscle strength and physical performance assessments and MRI. Creatinine to cystatin C ratio was calculated as (creatinine [mg/dL] / cystatin C [mg/L]) and low CCR were those in the lowest tertile (CCR < 8.16). Multivariable regression analyses were used to determine the associations of baseline CCR with muscle volumes and function 6.6 years later.

RESULTS

Baseline low CCR was associated with lower MRI-measured muscle volumes and poorer physical function 6.6 years later. Compared to high CCR group, mean fat-free thigh muscle volume of the low CCR group was 0.350 L lower (95% CI, 0.183-0.518) after adjustment for covariates. Similarly, the low CCR group was associated with 0.029 m/s slower (95% CI, 0.006-0.053) slower mean usual gait and 0.049 m/s slower (95% CI, 0.020-0.078) mean narrow gait speeds. CCR was not associated with handgrip strength and repeated chair stands and one-leg stand tests.

CONCLUSION

Low CCR at baseline was associated with lower fat-free muscle volumes and poorer gait speeds 6.6 years later. The potential of CCR as a predictive biomarker for adverse events related to sarcopenia in midlife women merits further investigation.

Genomic predictors of fat mass response to the standardized exercise training

To explore the genetic architecture underlying exercise-induced fat mass change, we performed a genome-wide association study with a Chinese cohort consisting of 442 physically inactive healthy adults in response to a 12-week exercise training (High-intensity Interval Training or Resistance Training). The inter-individual response showed an exercise-induced fat mass change and ten novel lead SNPs were associated with the response on the level of P<1×10-5. Four of them (rs7187742, rs1467243, rs28629770 and rs10848501) showed a consistent effect direction in the European ancestry. The Polygenic Predictor Score (PPS) derived from ten lead SNPs, sex, baseline body mass and exercise protocols explained 40.3% of the variance in fat mass response, meanwhile importantly the PPS had the greatest contribution. Of note, the subjects whose PPS was lower than -9.301 had the highest response in exercise-induced fat loss. Finally, we highlight a series of pathways and biological processes regarding the fat mass response to exercise, e.g. apelin signaling pathway, insulin secretion pathway and fat cell differentiation biological process.

History and perspectives on interval training in sport, health, and disease

Exercise can be conducted as low-intensity continuous training (LICT) or a variety of higher intensity work/rest formats, collectively called interval training. Interval training was developed for athletes in the early 20th century. It was systemized in Sweden as Fartlek, and in Germany as die interval Method, in the 1930s. Most contemporary forms of interval training evolved from these progenitors. In essence, interval training allows a large volume of high-intensity or race specific training to be performed while controlling the development of fatigue. Adding interval training to LICT done by athletes adds about 2%-4% to performance achievable with LICT, which represents a competitively meaningful difference in performance (e.g., 4:25 vs. 4:00 over 1 mile). More recently, interval training has been applied to health- fitness participants and even to patients with health conditions. Studies indicate that a comparatively low volume of interval training can produce substantial improvement in physiologic capacity, in as little as 20% of training time versus LICT. There are data indicating that interval training can be reasonably pleasant, have good adherence, and is safe, even in patients. Although interval training was originally designed for athletics, the fundamental patterns of work versus recovery are remarkably similar in healthy adults and patients. Although the total volume of training and both absolute and relative intensity and magnitude of homeostatic disturbance are larger in athletes, the overall pattern of effort is the same in fitness participants and patients. Interval training can thus be characterized as an important step in the evolution of exercise training.

Self-paced combined training alleviated oxidative stress, inflammatory responses and hyperlipidaemia in people living with multiple sclerosis: a randomised controlled trial

Objective: To examine the effects of self-paced combined high-intensity interval training and resistance training (HIIT-RT) on oxidative stress, inflammation lipid profile and body composition in people with multiple sclerosis (PwMS).

Methods: Twenty-three PwMS were randomly assigned to either a control group (CG, n = 12) or a training group (TG, n = 11). The TG performed a 12-week self-paced HIIT-RT (3 times/week). Biomarkers of oxidative stress, inflammation, lipid profile and cellular damage as well as body composition were assessed pre- and post- intervention.

Results: Comparatively with CG, the TG showed a decrease in advanced oxidation protein products (p = 0.002, Hedges'g (g) = 1.50) and total thiols (p = 0.0011, g = 1.57), as well as an increase in reduced glutathione (p = 0.03, g = 0.98). Neutrophils (p = 0.003, g = 1.38), lymphocytes (p = 0.038, g = 0.92) and low-density lipoprotein cholesterol (p < 0.001, g = 2.14) decreased in TG compared with CG. There was also a decrease in body weight (p = 0.003, g = 1.39), body mass index (p = 0.002, g = 1.45) and fat mass (p = 0.006, g = 1.27) in TG comparatively with CG.

Conclusion: This study revealed the effectiviness of self-paced HIIT-RT in alleviating oxidative stress, inflammatory responses and hyperlipidaemia, as well as in improving body composition in PwMS. This combined training may be recommended to better counteract the damage related to multiple sclerosis.

High-intensity interval training or lactate administration combined with aerobic training enhances visceral fat loss while promoting VMH neuroplasticity in female rats

BACKGROUND

High-intensity interval training (HIT) does not burn fat during exercise. However, it significantly reduces visceral adipose after long-term training. The underlying mechanism may be related to the elevation of fat consumption during the post-exercise recovery period, which is regulated by the hypothalamus-adipose axis. Lactate is a hallmark metabolite of high-intensity exercise, which could mediate significant neuroplasticity through the brain-derived neurotrophic factor (BDNF) pathway. However, whether HIT could enhance hypothalamus activity and adipose catabolism in the recovery period remains to be elucidated. Also, it is worth exploring whether adding lactate administration to prolonged, continuous submaximal aerobic training (AT) could simulate HIT-induced neuroplastic effects and fat loss.

METHODS

First, we compared the influence of 4-week HIT and aerobic training (AT) on the electrophysiology of the ventromedial hypothalamus (VMH), which is deeply involved in the regulation of lipolysis, as well as the 24-hour excess post-exercise oxygen consumption (EPOC), the fat oxidation rate and lipolysis. To further confirm whether excess lactate during AT could reproduce the effect of HIT, we also observed the effects of lactate infusion during AT (AT + Lac) on neuroplasticity and metabolism.

RESULTS

Four-week HIT induced higher BDNF expression and a higher neuronal spike firing rate in VMH than AT, accompanied by elevated EPOC, fat oxidation and visceral fat lipolysis. AT + Lac and HITT could induce similar hypothalamic and metabolic changes. However, power spectral density analysis of local field potentials (LFPs) showed that the AT + Lac group was affected in fewer frequency bands than the HIT group.

CONCLUSION

HIT-induced reduction of visceral fat was accompanied by increased VMH activity. Adding lactate administration to AT could partially reproduce hypothalamic plasticity and the metabolic effects of HIT. However, different band changes of LFPs implied that the neuronal subpopulations or pathways influenced by these two methods were not entirely consistent.

Suppressive effects of exercise-conditioned serum on cancer cells: A narrative review of the influence of exercise mode, volume, and intensity

Cancer is a major cause of morbidity and mortality worldwide, and the incidence is increasing, highlighting the need for effective strategies to treat this disease. Exercise has emerged as fundamental therapeutic medicine in the management of cancer, associated with a lower risk of recurrence and increased survival. Several avenues of research demonstrate reduction in growth, proliferation, and increased apoptosis of cancer cells, including breast, prostate, colorectal, and lung cancer, when cultured by serum collected after exercise in vitro (i.e., the cultivation of cancer cell lines in an experimental setting, which simplifies the biological system and provides mechanistic insight into cell responses). The underlying mechanisms of exercise-induced cancer suppressive effects may be attributed to the alteration in circulating factors, such as skeletal muscle-induced cytokines (i.e., myokines) and hormones. However, exercise-induced tumor suppressive effects and detailed information about training interventions are not well investigated, constraining more precise application of exercise medicine within clinical oncology. To date, it remains unclear what role different training modes (i.e., resistance and aerobic training) as well as volume and intensity have on exercise-conditioned serum and its effects on cancer cells. Nevertheless, the available evidence is that a single bout of aerobic training at moderate to vigorous intensity has cancer suppressive effects, while for chronic training interventions, exercise volume appears to be an influential candidate driving cancer inhibitory effects regardless of training mode. Insights for future research investigating training modes, volume and intensity are provided to further our understanding of the effects of exercise-conditioned serum on cancer cells.

A Worksite Intervention Program for Obese Sedentary Women Using Wearable Technology

BACKGROUND

The sedentary aspects of work have been associated with increased health risks. The purpose of this study was to compare the effects of high intensity interval training (HIIT) and increased steps on anthropometric, body mass, and body composition changes over a 12-week period.

METHODS

12 sedentary, obese, body mass index (BMI) = 32.98 ± 3.21 kg/m2, adult (46.10 ± 9.56 years), females volunteered for the study and were randomly assigned into one of the two groups, the HIIT group and the STEP group. During the 12-week study, all participants' movements were monitored during their workday, via an accelerometer, a Movband™, 5 days/week.

FINDINGS

The HIIT group (n = 5) engaged in structured exercise (~15.0 ± 3.5 minutes), defined as total body moves which consisted of eight different routines: upper and lower extremity, two cardio segments, two total body, yoga, and abdominal exercises. The STEP group (n = 7) averaged ~7,000 steps/day throughout 12 weeks. Pre- and post-program measurements included: five anthropometric measurements (biceps, waist, abdomen, hips, and thigh), along with body mass and body composition measures: relative (%) body fat via dual x-ray absorptiometry (DEXA) scan, fat mass, fat-free mass, and lean mass.

CONCLUSIONS

Statistical significance was determined among participants for biceps, hips, and thigh measurements along with body mass and body composition changes for improved health.

APPLICATION TO PRACTICE

This work is suggestive that a physical activity intervention integrated into the workplace via work processes and/or structured exercise is supportive in reducing anthropometric and body composition measurements, while changing body mass, to increase health and reduce obesity-related chronic disease risks in sedentary women.

The causality between leisure sedentary behaviors, physical activity and obstructive sleep apnea: a bidirectional Mendelian randomization study

Background

Previous observational studies have shown a correlation between leisure sedentary behaviors (LSB) and physical activity (PA) with the incidence of obstructive sleep apnea (OSA). However, the causal associations remain unknown. Therefore, our study used bidirectional two-sample Mendelian randomization (MR) to identify potential causal relationships between LSB/PA and OSA.

Methods

We sourced genetic variation data for LSB and PA from the UK Biobank, while data on OSA were collected from the FinnGen study. The primary analysis method employed was the inverse variance weighted (IVW) approach, complemented by the weighted median and MR-Egger methods. For sensitivity analyses, we conducted Cochran's Q test, the MR-Egger intercept test, the MR-PRESSO global test, and the leave-one-out analysis.

Results

IVW analyses showed that genetically predicted leisure television watching (odds ratio [OR] = 1.38, 95% confidence interval [CI] = 1.09-1.75, p = 0.007) and computer use (OR = 1.48, 95% CI = 1.15-1.92, p = 0.002) significantly increased the risk of OSA. Conversely, self-reported vigorous physical activity (VPA) (OR = 0.33, 95% CI = 0.11-0.98, p = 0.046) may reduce the risk of OSA. No causal effects on OSA risk were observed for driving or self-reported moderate-to-vigorous physical activity. Furthermore, the reverse MR analysis indicated no significant causal relationship between OSA and any LSB/PA phenotype. Sensitivity tests showed no significant heterogeneity or horizontal pleiotropy.

Conclusion

This study suggests that leisurely television watching and computer use are risk factors for OSA, while VPA may be a protective factor. Additionally, OSA does not affect PA or LSB levels. We recommend reducing sedentary activities, particularly television watching and computer use, and prioritizing VPA to reduce the risk of OSA. Further research in diverse populations and settings is needed to validate these findings.

Effects of a Cycling versus Running HIIT Program on Fat Mass Loss and Gut Microbiota Composition in Men with Overweight/Obesity

PURPOSE

High-intensity interval training (HIIT) can efficiently decrease total and (intra-)abdominal fat mass (FM); however, the effects of running versus cycling HIIT programs on FM reduction have not been compared yet. In addition, the link between HIIT-induced FM reduction and gut microbiota must be better investigated. The aim of this study was to compare the effects of two 12-wk HIIT isoenergetic programs (cycling vs running) on body composition and fecal microbiota composition in nondieting men with overweight or obesity.

METHODS

Sixteen men (age, 54.2 ± 9.6 yr; body mass index, 29.9 ± 2.3 kg·m -2 ) were randomly assigned to the HIIT-BIKE (10 × 45 s at 80%-85% of maximal heart rate, 90-s active recovery) or HIIT-RUN (9 × 45 s at 80%-85% of maximal heart rate, 90-s active recovery) group (3 times per week). Dual-energy x-ray absorptiometry was used to determine body composition. Preintervention and postintervention fecal microbiota composition was analyzed by 16S rRNA gene sequencing, and diet was controlled.

RESULTS

Overall, body weight, and abdominal and visceral FM decreased over time ( P < 0.05). No difference was observed for weight, total body FM, and visceral FM between groups (% change). Conversely, abdominal FM loss was greater in the HIIT-RUN group (-16.1% vs -8.3%; P = 0.050). The α-diversity of gut microbiota did not vary between baseline and intervention end and between groups, but was associated with abdominal FM change ( r = -0.6; P = 0.02). The baseline microbiota profile and composition changes were correlated with total and abdominal/visceral FM losses.

CONCLUSIONS

Both cycling and running isoenergetic HIIT programs improved body composition in men with overweight/obesity. Baseline intestinal microbiota composition and its postintervention variations were correlated with FM reduction, strengthening the possible link between these parameters. The mechanisms underlying the greater abdominal FM loss in the HIIT-RUN group require additional investigations.

Body composition, physical activity, and menopause symptoms: how do they relate?

OBJECTIVE

This study characterized the impact of physical activity (light, moderate, and vigorous [VIG] active minutes per day) and body composition (percent body fat [%BF] and fat-free mass index) on total menopausal symptoms (TMSs) in 72 premenopausal, perimenopausal (PERI), or postmenopausal women.

METHODS

Activity minutes were collected from wearable fitness trackers. Body composition was evaluated using a whole-body dual-energy x-ray absorptiometry scan. TMSs were quantified using The North American Menopause Society Questionnaire.

RESULTS

Significant associations were observed between TMSs and %BF ( r = 0.464, P < 0.001) and VIG ( r = -0.245, P = 0.038). %BF and VIG were significant predictors for TMSs across groups ( R2 = 0.146 and R2 = 0.092, respectively), but only %BF maintained for PERI ( R2 = 0.421, P < 0.001).

CONCLUSIONS

%BF predicted nearly half of the variance in PERI TMSs, whereas VIG predicted 9% of the sample variance, demonstrating an important influence of body fat accumulation and intense physical activity in the menopause transition. High-intensity exercise interventions to alleviate body composition changes may also reduce menopausal-related symptoms for PERI women.

Effects of various exercise types on visceral adipose tissue in individuals with overweight and obesity: A systematic review and network meta-analysis of 84 randomized controlled trials

The purpose of this systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) was to investigate the effects of various exercise categories on visceral adipose tissue (VAT) and other anthropometric variables in individuals with overweight and obesity. A total of 84 RCTs (4836 patients) were included. Aerobic exercise (AE) of at least moderate intensity, resistance training (RT), AE combined with RT (AE + RT), and high-intensity interval training (HIIT) were beneficial for reducing VAT. A subgroup analysis showed that RT improves VAT in males and those with BF% < 40% but not in females and those with body fat percentage (BF%) ≥ 40%. AE, RT, AE + RT, and HIIT significantly improved weight (except RT), total body fat (TBF), body mass index (BMI), waist circumference (WC), and subcutaneous adipose tissue (SAT). Surface under the cumulative ranking curve (SUCRA) probability ranking showed that AE with vigorous intensity and HIIT have the highest probability of being the best exercise intervention for improving VAT, weight, TBF, BMI, WC, and SAT. These findings suggest that regular exercise can improve VAT in individuals with overweight and obesity. AE of vigorous intensity and HIIT may be the best exercise treatment, and RT is the least effective intervention.

Anaerobic and aerobic contributions to repeated supramaximal cycling exercises and their adaptation to high-intensity interval training in obese perimenopausal and postmenopausal women

OBJECTIVE

This study investigated the anaerobic and aerobic contributions to total energy release during repeated supramaximal cycling exercises (SCE) and their adaptation in response to 6 weeks of high-intensity interval training (HIIT) in obese perimenopausal and postmenopausal women.

METHODS

Nineteen perimenopausal women and 21 postmenopausal women with an average age of 50.1 years participated in the 6-week HIIT intervention. Before and after the training, the accumulated oxygen deficits (mL·min -1 ) and anaerobic and aerobic contributions (%) were measured in all groups via repeated SCE.

RESULTS

The results showed that, before training, the anaerobic contributions to repeated SCE did not differ between the perimenopausal and postmenopausal women for the first three repetitions. However, a higher decrease was reported for postmenopausal women at the fourth and fifth repetitions ( P < 0.01, respectively). After HIIT, anaerobic contributions increased significantly in both groups ( P < 0.01, respectively). Nevertheless, postmenopausal women still had significantly lower anaerobic contributions to repeated SCE compared with perimenopausal women ( P < 0.01, respectively). Multiple linear regression analysis indicated that menopause status was an independent predictor of anaerobic contribution, accounting for 17%, 21%, 15%, 19%, and 22% of variations (β = 0.28, P = 0.03; β = 0.29, P = 0.04; β = 0.18, P = 0.05; β = 0.22, P = 0.05; and β = 0.33, P = 0.03 for the first to the fifth repetitions consecutively for perimenopausal vs postmenopausal groups).

CONCLUSIONS

A 6-week HIIT intervention increased the anaerobic contributions to energy in response to repeated SCE in obese perimenopausal and postmenopausal women. However, postmenopausal women had lower anaerobic contributions at the fourth and fifth repetitions mainly due to the effects of menopause.

Intravoxel incoherent motion imaging to assess the acute effects of moderate-intensity continuous training and high-intensity interval training on thigh muscles

This study investigated the use of intravoxel incoherent motion imaging (IVIM) to compare skeletal muscle perfusion during and after high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) to determine the impact on fat oxidation outcomes. Twenty overweight volunteers were recruited for the study. Each participant received one HIIT intervention and one MICT intervention using a cycling ergometer. Participants underwent a magnetic resonance imaging scan before, immediately after, and 1 and 2 h after each intervention. The IVIM parameters (D, fD*) of the rectus femoris, vastus lateralis, and biceps femoris long head were obtained. Changes in IVIM parameters of these muscles after both exercise interventions were compared using a two-factor repeated measures analysis of variance. In the rectus femoris, the fD* increased immediately after exercise intervention (d = 0.69 × 10-3  mm2 /s, p < 0.0083) and 2 h after exercise intervention (d = 0.64 × 10-3  mm2 /s, p < 0.0083) compared with before exercise. The increase in the fD* in the HIIT group was greater than that in the MICT group (d = 0.32, p = 0.023). In the vastus lateralis, the fD* increased immediately after the exercise intervention (d = 0.53 × 10-3  mm2 /s, p < 0.001) and returned to the pre-exercise level 1 h after exercising. The increase in the fD* in the HIIT group was lower than that in the MICT group (d = -0.21, p = 0.015). For the biceps femoris long head, the fD* was not significantly different between the two exercise interventions before and after exercise. Furthermore, the fD* 60 min after the HIIT intervention correlated with maximal oxygen consumption (VO2max), whereas fD* immediately after the MICT intervention correlated with VO2max. In summary, IVIM parameters can be used to evaluate differences in muscle perfusion between HIIT and MICT, and show a correlation with VO2max.

The acute effects of exercise intensity and inorganic nitrate supplementation on vascular health in females after menopause

Menopause is associated with reduced nitric oxide bioavailability and vascular function. Although exercise is known to improve vascular function, this is blunted in estrogen-deficient females post-menopause (PM). Here, we examined the effects of acute exercise at differing intensities with and without inorganic nitrate (NO3-) supplementation on vascular function in females PM. Participants were tested in a double-blinded, block-randomized design, consuming ∼13 mmol NO3- in the form of beetroot juice (BRJ; n = 12) or placebo (PL; n = 12) for 2 days before experimental visits and 2 h before testing. Visits consisted of vascular health measures before (time point 0) and every 30 min after (time points 60, 90, 120, 150, and 180) calorically matched high-intensity exercise (HIE), moderate-intensity exercise (MIE), and a nonexercise control (CON). Blood was sampled at rest and 5-min postexercise for NO3-, NO2-, and ET-1. BRJ increased N-oxides and decreased ET-1 compared with PL, findings which were unchanged after experimental conditions (P < 0.05). BRJ improved peak Δflow-mediated dilation (FMD) compared with PL (P < 0.05), defined as the largest ΔFMD for each individual participant across all time points. FMD across time revealed an improvement (P = 0.05) in FMD between BRJ + HIE versus BRJ + CON, while BRJ + MIE had medium effects compared with BRJ + CON. In conclusion, NO3- supplementation combined with HIE improved FMD in postmenopausal females. NO3- supplementation combined with MIE may offer an alternative to those unwilling to perform HIE. Future studies should test whether long-term exercise training at high intensities with NO3- supplementation can enhance vascular health in females PM.NEW & NOTEWORTHY This study compared exercise-induced changes in flow-mediated dilation after acute moderate- and high-intensity exercise in females postmenopause supplementing either inorganic nitrate (beetroot juice) or placebo. BRJ improved peak ΔFMD postexercise, and BRJ + HIE increased FMD measured as FMD over time. Neither PL + MIE nor PL + HIE improved FMD. These findings suggest that inorganic nitrate supplementation combined with high-intensity exercise may benefit vascular health in females PM.

Effect of high-intensity interval training compared to moderate-intensity continuous training on body composition and insulin sensitivity in overweight and obese adults: A systematic review and meta-analysis

Objective

To compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on adults with overweight and obesity. Outcomes, including changes in insulin sensitivity, weight, body mass index (BMI), waist circumference, and body fat, were analyzed.

Methods

A systematic literature review was conducted. This review is registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42021281899. Clinical trials involving individuals who are overweight and obese and comparing HIIT with MICT effects on insulin sensitivity, weight, BMI, body fat percentage, and waist circumference were included. PubMed, Web of Science, Embase, and Scopus databases were searched using controlled vocabulary and free-text terms related to HIIT, obesity, and overweight. The search included studies published until September 2022. The Rob2 tool was used to assess the risk of bias. The results were presented through meta-analyses that provided summary estimators and confidence intervals. Subgroup analyses were conducted to assess the effect of the risk of bias on the outcomes. This research did not receive any specific funding.

Results

Of the 2534 articles, 30 met the eligibility criteria. The intervention duration ranged from 4 to 16 weeks. The observed effects for each outcome were as follows: insulin sensitivity (p = 0.02), weight (p = 0.58), BMI (p = 0.53), waist circumference (p = 0.87), body fat percentage (p = 0.07), body fat mass in kilograms (p = 0.39). The level of evidence obtained was moderate except for waist circumference, which was rated as low. Limitations included heterogeneity in training protocols, measurements, and study duration. Additionally, a risk of bias was identified in these studies.

Conclusion

HIIT and MICT did not significantly differ in their effects on weight, BMI, waist circumference, or body fat mass in adults with overweight and obesity. However, a moderate beneficial effect of HIIT was observed on insulin sensitivity. Therefore, further evidence is required to confirm these findings.

Effect of resistance training on lipid profile in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Physical exercise decreases cardiovascular risk and can alter the lipid profile in postmenopausal women. Although it is believed that resistance training can potentially decrease serum lipid levels in postmenopausal females, the evidence remains inconclusive. The aim of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to clarify the impact of resistance training on the lipid profile in postmenopausal women.

METHODS

Web of Science, Scopus, PubMed/Medline and Embase were searched. RCTs that evaluated the effect of resistance training on total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels were included in this review. Effect size was estimated using the random effects model. Subgroup analyses based on age, duration of intervention, pre-enrolment serum lipid levels and body mass index were performed.

RESULTS

Data pooled from 19 RCTs revealed that resistance training can reduce TC [weighted mean difference (WMD) -11.47 mg/dl; p = 0.002], LDL-C (WMD -8.48 mg/dl; p = 0.01) and TG (WMD -6.61 mg/dl; p = 0.043) levels. TC levels decreased particularly in subjects aged < 60 years (WMD -10.77 mg/dl; p = 0.003), in RCTs lasting < 16 weeks (WMD -15.70 mg/dl; p = 0.048), and in subjects with hypercholesterolaemia (WMD -12.36 mg/dl; p = 0.001) or obesity (WMD -19.35 mg/dl; p = 0.006) before RCT enrolment. There was a significant decrease in LDL-C (WMD -14.38 mg/dl; p = 0.002) levels in patients with LDL-C ≥ 130 mg/dl before trial enrolment. Resistance training reduced HDL-C (WMD -2.97 mg/dl; p = 0.01) levels particularly in subjects with obesity. TG (WMD -10.71 mg/dl; p = 0.01) levels decreased particularly when the intervention lasted < 16 weeks.

CONCLUSION

Resistance training can decrease TC, LDL-C and TG levels in postmenopausal females. The impact of resistance training on HDL-C levels was small, and was only observed in individuals with obesity. The effect of resistance training on the lipid profile was more notable in short-term interventions and in postmenopausal women with dyslipidaemia or obesity before trial enrolment.

Effects of increasing light versus moderate-to-vigorous physical activity on cardiometabolic health in Chinese adults with obesity

Increasing daily physical activity (PA) is a practical way to decrease the risk of cardiometabolic diseases, while the studies on exercise intensity remain limited. The purpose of the present study was to compare the effects of increasing light PA (LPA) or moderate-to-vigorous PA (MVPA) for 12 weeks on cardiometabolic markers in Chinese adults with obesity. Fifty-three adults were randomly assigned to the 1) control group, 2) LPA group, and 3) MVPA group in free-living settings. The intervention effects on body composition, cardiorespiratory fitness, and cardiometabolic biomarkers were analysed using a generalized estimated equation model adjusted for baseline values and potential confounders. Compared with the control group, the MVPA group showed improvements in body composition, lipids, C-peptide, monocyte chemoattractant protein-1 (MCP-1), interleukin-8, leptin, and E-selectin. A favourable change in triglycerides and E-selectin were observed in the LPA group when compared to the control group. Lastly, improvements in waist circumference, C-reactive protein, and MCP-1 were observed in the MVPA group when compared to those in the LPA group. Although increasing both LPA and MVPA improved certain cardiometabolic biomarkers, the latter may have more benefits. These findings imply that MVPA may reduce cardiometabolic disease risk more effectively than LPA, especially in Chinese adults with obesity.

Adipocyte Metabolism and Health after the Menopause: The Role of Exercise

Postmenopausal women represent an important target population in need of preventative cardiometabolic approaches. The loss of estrogen following the menopause eliminates protections against metabolic dysfunction, largely due to its role in the health and function of adipose tissue. In addition, some studies associate the menopause with reduced physical activity, which could potentially exacerbate the deleterious cardiometabolic risk profile accompanying the menopause. Meanwhile, exercise has adipocyte-specific effects that may alleviate the adverse impact of estrogen loss through the menopausal transition period and beyond. Exercise thus remains the best therapeutic agent available to mitigate menopause-associated metabolic dysfunction and represents a vital behavioral strategy to prevent and alleviate health decline in this population.

Exercise effect on the gut microbiota in young adolescents with subthreshold depression: A randomized psychoeducation-controlled Trial

This 3-month randomized psychoeducation-controlled trial (RCT) of exercise was undertaken in young adolescents with subthreshold depression to examine the impact on gut microbiota. Participants (aged 12-14 years) were randomly assigned to an exercise or a psychoeducation-controlled group. The exercise intervention arm took moderate-intensity exercise, comprised of 30 min of running per day, 4 days a week for 3 months. Psychoeducation intervention consisted of 6 sessions of group activity including gaming, reading, and singing. The gut microbiota was assessed by metagenomic sequencing. After 3-month moderate-intensity exercise, the intervention group increased the relative abundance of Coprococcus, Blautia, Dorea, Tyzzerella at the genus level, as well as Tyzzerella nexilis, Ruminococcus obeum at species level when compared to the psychoeducation-controlled group. Moreover, EggNOG analyses showed that the defense and signal transduction mechanism were highly enriched after the active intervention, and changes were correlated with improvements in depressive symptoms measured by Chinese Patient Depression Questionnaire 9. The KEGG pathway of neurodegenerative diseases was depleted in the microbiome in young adolescents with subthreshold depression after exercise intervention. This 3-month RCT suggests that at both the genus and species levels, aerobic group exercise intervention improved in depressive symptoms and revealed changes in gut microbiota suggesting beneficial effects.

Comparison of the Effect of Endurance, Strength and Endurance-Strength Training on Glucose and Insulin Homeostasis and the Lipid Profile of Overweight and Obese Subjects: A Systematic Review and Meta-Analysis

The most effective type of training to improve cardiometabolic parameters in overweight subjects is unknown. This meta-analysis compared the effect of endurance, strength and combined training on glucose, insulin metabolism and the lipid profile of overweight and obese adults. The Cochrane, PubMed, Scopus and Web of Science databases were searched to identify randomised trials assessing the effect of training intervention on fasting and 2 h glucose and insulin levels, glycated haemoglobin (HbA1c), homeostatic model assessment of insulin resistance (HOMA), C-peptide, total cholesterol (TC), low- (LDL-C) and high-density lipoprotein cholesterol and triglycerides (TG). Forty-six studies were included showing that endurance training more favourably reduced HbA1c (p = 0.044), and LDL-C (p = 0.021) than strength training. Endurance-strength training more effectively decreased glucose (p = 0.002), HbA1c (p = 0.032), HOMA (p = 0.002), TC (p = 0.039), LDL-C (p = 0.046), HDL (p = 0.036) and TG levels (p = 0.025) than strength training. Combined training significantly reduced the HOMA index (p = 0.009) and TG levels (p = 0.039) compared with endurance training. Endurance and endurance-strength training have a more favourable effect on glucose and insulin homeostasis and lipid profile than strength training in overweight and obese adults. However, the results from this meta-analysis should be interpreted cautiously due to significant heterogeneity among included studies.

Effects of 12 weeks of aerobic exercise combined with resistance training on neurocognitive performance in obese women

Background/Objectives

To the best of our knowledge, there have been no previous studies conducted on the long-term effects of an exercise intervention on deficits in inhibitory control in obese individuals. The aim of this study was thus to examine the effect of 12 weeks of a combination of aerobic and resistance exercise on behavioral and cognitive electrophysiological performance involving cognitive interference inhibition in obese individuals.

Methods

Thirty-two qualified healthy obese women were randomly divided into either an exercise group (EG, age: 34.76 ± 5.52 years old; BMI: 29.35 ± 3.52 kg/m2) or a control group (CG, age: 33.84 ± 7.05 years old; BMI: 29.61 ± 4.31 kg/m2). All participants performed the Stroop task, with electrophysiological signals being collected simultaneously before and after a 12-week intervention. The estimated V̇O2max, muscular strength, and body fat percentage (measured with dual-energy X-ray absorptiometry) were also assessed within one week before and after the intervention. Participants in the EG group engaged in 30 min of moderate-intensity aerobic exercise combined with resistance exercise, 5 sessions per week for 12 weeks, while the participants in the CG group maintained their regular lifestyle without engaging in any type of exercise.

Results

The results revealed that although a 12-week exercise intervention did not enhance the behavioral indices [e.g., accuracy rates (ARs) and reaction times (RTs)] in the EG group, significantly shorter N2 and P3 latencies and greater P2 and P3 amplitudes were observed. Furthermore, the fat percentage distribution (e.g. total body fat %, trunk fat %, and leg fat %) and level of physical fitness (e.g. estimated V̇O2max and muscular strength) in the EG group were significantly improved. The changes prior to and after the intervention in the P3 amplitude and trunk fat percentage were significantly negatively correlated in the EG group (r = -0.521, p = 0.039).

Conclusions

These findings suggested that 12 weeks of aerobic exercise combined with resistance exercise in obese women affects cognitive function broadly, but not specifically in terms of inhibitory control. The percentage of decreased trunk fat may play a potential facilitating role in inhibition processing in obesity.

Associations of resting and peak fat oxidation with sex hormone profile and blood glucose control in middle-aged women

BACKGROUND AND AIMS

Menopause may reduce fat oxidation. We investigated whether sex hormone profile explains resting fat oxidation (RFO) or peak fat oxidation (PFO) during incremental cycling in middle-aged women. Secondarily, we studied associations of RFO and PFO with glucose regulation.

METHOD AND RESULTS

We measured RFO and PFO of 42 women (age 52-58 years) with indirect calorimetry. Seven participants were pre- or perimenopausal, 26 were postmenopausal, and nine were postmenopausal hormone therapy users. Serum estradiol (E2), follicle-stimulating hormone, progesterone, and testosterone levels were quantified with immunoassays. Insulin sensitivity (Matsuda index) and glucose tolerance (area under the curve) were determined by glucose tolerance testing. Body composition was assessed with dual-energy X-ray absorptiometry; physical activity with self-report and accelerometry; and diet, with food diaries. Menopausal status or sex hormone levels were not associated with the fat oxidation outcomes. RFO determinants were fat mass (β = 0.44, P = 0.006) and preceding energy intake (β = -0.40, P = 0.019). Cardiorespiratory fitness (β = 0.59, P = 0.002), lean mass (β = 0.49, P = 0.002) and physical activity (self-reported β = 0.37, P = 0.020; accelerometer-measured β = 0.35, P = 0.024) explained PFO. RFO and PFO were not related to insulin sensitivity. Higher RFO was associated with poorer glucose tolerance (β = 0.52, P = 0.002).

CONCLUSION

Among studied middle-aged women, sex hormone profile did not explain RFO or PFO, and higher fat oxidation capacity did not indicate better glucose control.

Effects of high-intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise: a systematic review and meta-analysis

OBJECTIVE

To investigate the effects of high-intensity interval training (HIIT) and sprint interval training (SIT) on fat oxidation during exercise (FatOx) and how they compare with the effects of moderate-intensity continuous training (MICT).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Academic Search Ultimate, CINAHL, Networked Digital Library of Theses and Dissertations, Open Access Theses and Dissertations, OpenDissertations, PubMed/MEDLINE, Scopus, SPORTDiscus and Web of Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies using a between-group design, involving adult participants who were not trained athletes, and evaluating effects of HIIT or SIT on FatOx (vs no exercise or MICT) were included.

RESULTS

Eighteen studies of fair-to-good quality were included; nine comparing HIIT or SIT with no exercise and eleven comparing HIIT or SIT with MICT. A significant pooled effect of these types of interval training on FatOx was found (mean difference in g/min (MD)=0.08; 95% confidence interval (CI) 0.04 to 0.12; p<0.001). Significant effects were found for exercise regimens lasting ≥4 weeks, and they increased with every additional week of training (β=0.01; 95% CI 0.00 to 0.02; p=0.003). HIIT and/or SIT were slightly more effective than MICT (MD=0.03; 95% CI 0.01 to 0.05; p=0.005). The effects on FatOx were larger among individuals with overweight/obesity.

CONCLUSION

Engaging in HIIT or SIT can improve FatOx, with larger effects expected for longer training regimens and individuals with overweight/obesity. While some effects seem small, they may be important in holistic approaches to enhance metabolic health and manage obesity.

Impact of High-Intensity Interval Training on Body Composition and Depressive Symptoms in Adults under Home Confinement

The home confinement derived from the COVID-19 pandemic has led to drastic changes in people’s habits. This situation has influenced their eating, rest, physical activity and socialization patterns, triggering changes in their mental stability. It was demonstrated that physical activity is beneficial for people’s physical and mental health. By its moderate volume and requiring little space or material, high-intensity interval training (HIIT) could prove to be a valid alternative in a situation of confinement. The aim of the present study was to observe the impact of an 8-week HIIT protocol on the body composition and the depressive symptoms of adults in strict home confinement. A total of 21 healthy adults, both male and female, (35.4 ± 5.6 years old; 70.50 ± 12.1 kg; 171 ± 10 cm) were divided into an experimental group (EG, n = 11) who carried out an 8-week Tabata protocol, based upon calisthenic exercises with their own weight in their homes, and a control group (CG, n = 10) who did not carry out any systematic physical activity over the same period. Following the intervention, the EG experienced a significant reduction in percentage (t = 3.86, d = 0.57, p < 0.05) and in kg (t = 4.62, d = 0.29, p < 0.05) of body fat mass (BFM) and body fat mass index (BFMI) (t = 4.61, d = 0.31, p < 0.05), as well as a reduction in depressive symptoms (t = 6.48, d = 1.3, p < 0.05). These results indicate that HIIT is a potential public health tool that could possibly be prescribed to the population in case of future situations of home confinement.

High Intensity Interval Training: A Potential Method for Treating Sarcopenia

Sarcopenia, an age-related disease characterized by loss of muscle strength and muscle mass, has attracted the attention of medical experts due to its severe morbidity, low living quality, high expenditure of health care, and mortality. Traditionally, persistent aerobic exercise (PAE) is considered as a valid way to attenuate muscular atrophy. However, nowadays, high intensity interval training (HIIT) has emerged as a more effective and time-efficient method to replace traditional exercise modes. HIIT displays comprehensive effects on exercise capacity and skeletal muscle metabolism, and it provides a time-out for the recovery of cardiopulmonary and muscular functions without causing severe adverse effects. Studies demonstrated that compared with PAE, HIIT showed similar or even higher effects in improving muscle strength, enhancing physical performances and increasing muscle mass of elder people. Therefore, HIIT might become a promising way to cope with the age-related loss of muscle mass and muscle function. However, it is worth mentioning that no study of HIIT was conducted directly on sarcopenia patients, which is attributed to the suspicious of safety and validity. In this review, we will assess the effects of different training parameters on muscle and sarcopenia, summarize previous papers which compared the effects of HIIT and PAE in improving muscle quality and function, and evaluate the potential of HIIT to replace the status of PAE in treating old people with muscle atrophy and low modality; and point out drawbacks of temporary experiments. Our aim is to discuss the feasibility of HIIT to treat sarcopenia and provide a reference for clinical scientists who want to utilize HIIT as a new way to cope with sarcopenia.

Examining effects of habitual physical activity and body composition on bone structure in early post-menopausal women: a pQCT analysis

After menopause, bones decline in structure and can break more easily. Physical activity can strengthen bones. This study investigated how activity and body composition can impact bone structure in post-menopausal women. Higher levels of physical activity were positively associated with bone structure at the lower leg.

PURPOSE

The menopausal transition is characterized by dramatic bone loss, leading to an increased risk of fracture. Few studies have examined how modifiable risk factors influence bone structure. Thus, the objective of this cross-sectional study was to examine the relationship between habitual physical activity (PA), body composition, and bone structure in post-menopausal women with low bone mass.

METHODS

Data was analyzed from 276 post-menopausal women with low bone mass enrolled in the Heartland Osteoporosis Prevention Study. Body composition and bone structure measures were collected using dual X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) at the tibia. Habitual PA was collected using the Human Activity Profile questionnaire. Multiple regression analysis was used to determine the relative impact of habitual PA and body composition on bone structure measures (density, area, and strength). Direct and/or indirect effects of PA on bone outcomes were assessed by path analysis.

RESULTS

Mean (± SD) age of participants was 54.5 (± 3.2) years and average BMI was 25.7 (± 4.7). Mean T-score of the total lumber spine and hip were - 1.5 (± .6) and - 0.8 (± .59), respectively, with all women classified with low bone mass. Habitual PA had a significant positive effect on bone area and strength measures at the 66% site, and trend effects at the 4% site. Lean mass had a significant positive effect on area and strength at the 66% site and 4% site. Fat mass showed no effect at the 66% site, with a positive effect on density and strength at the 4% site.

CONCLUSION

Increased habitual activity was related to improved bone structure of the tibia. Our results in post-menopausal women emphasize that PA and lean mass preservation are important for maintaining bone structure in the years following menopause.

Physiological Responses to Low-Volume Interval Training in Women

Interval training is a form of exercise that involves intermittent bouts of relatively intense effort interspersed with periods of rest or lower-intensity exercise for recovery. Low-volume high-intensity interval training (HIIT) and sprint interval training (SIT) induce physiological and health-related adaptations comparable to traditional moderate-intensity continuous training (MICT) in healthy adults and those with chronic disease despite a lower time commitment. However, most studies within the field have been conducted in men, with a relatively limited number of studies conducted in women cohorts across the lifespan. This review summarizes our understanding of physiological responses to low-volume interval training in women, including those with overweight/obesity or type 2 diabetes, with a focus on cardiorespiratory fitness, glycemic control, and skeletal muscle mitochondrial content. We also describe emerging evidence demonstrating similarities and differences in the adaptive response between women and men. Collectively, HIIT and SIT have consistently been demonstrated to improve cardiorespiratory fitness in women, and most sex-based comparisons demonstrate similar improvements in men and women. However, research examining insulin sensitivity and skeletal muscle mitochondrial responses to HIIT and SIT in women is limited and conflicting, with some evidence of blunted improvements in women relative to men. There is a need for additional research that examines physiological adaptations to low-volume interval training in women across the lifespan, including studies that directly compare responses to MICT, evaluate potential mechanisms, and/or assess the influence of sex on the adaptive response. Future work in this area will strengthen the evidence-base for physical activity recommendations in women.

Effects of Circuit Resistance Training on Body Composition, Strength, and Cardiorespiratory Fitness in Middle-Aged and Older Women: A Systematic Review and Meta-Analysis

A systematic review with meta-analysis was conducted to evaluate the effects of circuit resistance training (CRT) on cardiorespiratory fitness, strength, and body composition in middle-aged and older women. Sixteen studies were included in the meta-analysis. The CRT interventions led to a significant decrease in weight, body mass index, and fat mass along with an increase in muscle mass. Significant differences were found in the fat mass and a trend to develop muscle mass when compared with the control group. CRT led to a significant increase in VO2max, walking endurance, and time to exhaustion; likewise, significant differences were observed when compared with the control group. CRT had a moderate and large favorable effect on arm, trunk, and lower limb strength. Furthermore, the increases in strength observed in the CRT were significantly greater than the changes observed in the control group. In middle-aged and older women, CRT improved cardiorespiratory fitness and strength and optimized body composition.

Impact of Concurrent Training on Body Composition and Gut Microbiota in Postmenopausal Women with Overweight or Obesity

PURPOSE

Menopause tends to be associated with an increased risk of obesity and abdominal fat mass (FM) and is associated with lower intestinal species diversity. The aim of this study was to determine the effects of a high-intensity interval training and resistance training (HIIT + RT) program on body composition and intestinal microbiota composition in overweight or obese postmenopausal women.

METHODS

Participants (n = 17) were randomized in two groups: HIIT + RT group (3 × / week, 12 weeks) and control group without any training. Dual-energy X-ray absorptiometry was used to measure whole-body and abdominal/visceral FM and fat-free mass. Intestinal microbiota composition was determined by 16S rRNA gene sequencing at baseline and at the study end, and the diet controlled.

RESULTS

Compared with sedentary controls, physical fitness (Maximal Oxygen Consumption, Peak Power Output) increased, total abdominal and visceral FM decreased, and segmental muscle mass increased in the training group. Although the HIIT + RT protocol did not modify α-diversity and taxonomy, it significantly influenced microbiota composition. Moreover, various intestinal microbiota members were correlated with HIIT + RT-induced body composition changes, and baseline microbiota composition predicted the response to the HIIT + RT program.

CONCLUSIONS

HIIT + RT is an effective modality to reduce abdominal/visceral FM and improve physical capacity in non-dieting overweight or obese postmenopausal women. Training modified intestinal microbiota composition and the response to training seems to depend on the initial microbiota profile. More studies are needed to determine whether microbiota composition could predict the individual training response.

Bibliometric Review to Explore Emerging High-Intensity Interval Training in Health Promotion: A New Century Picture

Background: High-intensity interval training (HIIT) is an emerging exercise strategy and is considered to be a recipe for health promotion. This study aimed to systematically identify collaboration networks, track research trends, highlight current hotspots, and predict future frontiers in HIIT and its applications in health promotion since the start of the new century. Methods: Relevant original publications were obtained from the Science Citation Index Expanded of the Web of Science Core Collection (WoSCC) database between 2001 and 2020. CiteSpace and VOSviewer software were used to perform bibliometric visualization and comparative analysis of involved indexes that included countries, institutions, journals, authors, references, and keywords. Results: A total of 572 papers were included, and the trend of annual publications showed a remarkable growth. The United States and the University of Exeter were the most productive country and institutions, respectively, with 107 and 18 publications, respectively. European Journal of Applied Physiology took the lead in the number of published articles, and Medicine and Science in Sports and Exercise ranked first in the cocitation counts. Barker AR and Gibala MJ were considered as the most productive and the most highly-cited authors. Conclusions: "Health risks," "adolescent," and "aging" are the three noteworthy topics during the evolution of HIIT-health promotion (HIIT-HP) research. The current research hotspots of HIIT and its practices in the health promotion domain lies in "metabolic diseases," "cardiovascular diseases," "neurological diseases," and "musculoskeletal diseases." The authors summarize that "prevention and rehabilitation," "micro and molecular level," and "cognition and mental health" are becoming frontiers and focus on the health topics related to HIIT in the upcoming years, which are worthy of further exploration.

Aerobic exercise attenuates the effects of ovariectomy and sedentarism on body composition and food intake in female rats

ABSTRACT Objective To evaluate the impact of low to moderate aerobic exercise and ovariectomy on body composition and food consumption in female rats. Methods Forty adult Wistar female rats (age: 23 weeks; body weight: 275.2±3.6g; mean±SEM) were divided into 4 groups (n=10): laparotomy-sedentary; laparotomy-exercised; ovariectomy-sedentary; and ovariectomy-exercised. The exercised groups were submitted to a treadmill running program (16m/min; 30min/day, 5 days/week), for 8 weeks. Body weight and food consumption were monitored during the experiment. Visceral fat and carcass water, protein, ash, fat and carbohydrate fractions were analyzed. Two-way ANOVA plus the Tukey’s post hoc test was used for comparisons and p<0.05 was considered significant. Results The ovariectomized (ovariectomy-sedentary+ovariectomy-exercised) and sedentary (laparotomy-sedentary+ovariectomy-sedentary) animals showed higher (p<0.05) weight gain, food consumption, food efficiency ratio and weight gain/body weight ratio than laparotomy animals (laparotomy-sedentary+laparotomy-exercised) and exercised (exercised laparotomy+exercised ovariectomy), respectively. The ovariectomized and sedentary animals showed higher (p<0.05) carcass weight, fat percentage and visceral fat than laparotomy and exercised rats, respectively. Conclusion Ovariectomy and physical inactivity increase obesogenic indicators, whereas regular aerobic exercise of low to moderate intensity attenuates these unfavorable effects in female rats.

Acute metabolic responses after continuous or interval exercise in post-menopausal women with overweight or obesity

This pilot study compared the effects of acute high-intensity intermittent exercise (HIIE) and moderate-intensity continuous exercise (MICE) on post-exercise VO₂ , fat utilization, and 24-hours energy balance to understand the mechanism of higher fat mass reduction observed after high-intensity interval training in post-menopausal women with overweight/obesity. 12 fasted women (59.5 ± 5.8 years; BMI: 28.9 ± 3.9 kg·m^-2 ) completed three isoenergetic cycling exercise sessions in a counterbalanced, randomized order: (a) MICE [35 minutes at 60%-65% of peak heart rate, HR_max ], (b) HIIE 1 [60 × (8-s cycling-12-s recovery) at 80%-90% of HR_max ], and (c) HIIE 2 [10 × 1min at 80%-90% of HR_max  - 1-min recovery]. Then, VO₂ and fat utilization measured at rest and during the 2 hours post-exercise, enjoyment, perceived exertion, and appetite recorded during the session and energy intake (EI) and energy expenditure (EE) assessed over the next 24 hours were compared for the three modalities. Overall, fat utilization increased after exercise. No modality effect or time-modality interaction was observed concerning VO₂ and fat oxidation rate during the 2 hours post-exercise. The two exercise modalities did not induce specific EI and EE adaptations, but perceived appetite scores at 1 hour post-exercise were lower after HIIE 1 and HIIE 2 than MICE. Perceived exertion was higher during HIIE 1 and HIIE 2 than MICE, but enjoyment did not differ among modalities. The acute HIIE responses did not allow explaining the greater fat mass loss observed after regular high-intensity interval training in post-menopausal women with overweight/obesity. More studies are needed to understand the mechanisms involved in such adaptations.

Comparison of performance and health indicators between perimenopausal and postmenopausal obese women: the effect of high-intensity interval training (HIIT)

OBJECTIVE

This study examined the effects of 6 weeks of high-intensity interval training (HIIT) on performance and health indicators in obese perimenopausal (PERIM) women and similarly aged and older postmenopausal women (POSTM1 and POSTM2, respectively).

METHODS

Sixteen PERIM women (average age 49.6 y), 21 POSTM1 women (average age 50.6 y), and 19 POSTM2 women (average age 69.6 y) completed a 6-week HIIT intervention. Anthropometric parameters, mechanical efficiency (ME in %), lipid oxidation (LO in %), and low and high spectral frequencies (LF[ms2] and HF[ms2]) were computed pre- and postintervention.

RESULTS

PERIM women showed a significantly higher VO2max preintervention compared to POSTM1 and 2 (P < 0.01). Moreover, HF, LF, and the LF/HF ratio differed significantly in PERIM women preintervention compared to POSTM1 and 2 (P < 0.01, respectively). After 6 weeks, a significant decrease in anthropometric variables was observed for all groups (P < 0.01). The VO2max in mL/kg/min increased for all groups (P < 0.01). Multiple linear regression analysis demonstrated that age contributed significantly to differences in VO2max values between groups preintervention (r = 0.72). This model accounted for 34% (r2 = 0.34) of the variation. On the other hand, menopause status was an independent predictor of LO, accounting for 38% of the variation, as well as of HF (33%), LF (29%), and the LF/HF ratio (24%). After HIIT, no age or menopause effect was detected for these independent variables.

CONCLUSIONS

Maximal oxygen consumption, HF, LF, and the LF/HF ratio differ among women according to the menopausal status and age. A 6-week HIIT intervention improved many health and performance parameters and reduced the effects of menopause and age.

Land vs. water HIIE effects on muscle oxygenation and physiological parameter responses in postmenopausal women

Muscle oxygenation (MO) status is the dynamic balance between O₂ utilization and O₂ delivery. Low-impact high-intensity interval exercise MO responses in the exercise and recovery stage are still unclear. We compared the differences in MO and physiological parameters between high-intensity interval water-based exercise (WHIIE) and high-intensity interval land bike ergonomic exercise (LBEHIIE) in postmenopausal women. Eleven postmenopausal women completed WHIIE or LBEHIIE in counter-balanced order. Eight sets were performed and each exercise set included high intensity with 80% heart rate reserve (HRR) in 30 s and dynamic recovery with 50% HRR in 90 s. Muscle tissue oxygen saturation index (TSI), total hemoglobin (tHb), oxy-hemoglobin (O₂Hb), and deoxy-hemoglobin (HHb) were recorded. Blood lactate, heart rate and rating of perceived exertion (RPE) were measured at pre and post-exercise. Under similar exercise intensity, RPE in WHIIE was lower than that in LBEHIIE. The heart rate in WHIIE was lower than that in LBEHIIE at 1 and 2 min post-exercise. During the dynamic recovery, TSI, tHb, and O2Hb in water were higher than on land. A negative correlation was found between the change in TSI and lactate concentration (r = − 0.664). WHIIE produced greater muscle oxygenation during dynamic recovery. Muscle TSI% was inversely related to blood lactate concentration during exercise in water.

Effect of high intensity interval training on body composition in women before and after menopause: a meta-analysis

NEW FINDINGS

What is the topic of this review? A meta-analysis of the efficacy of high intensity interval training (HIIT) in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. What advances does it highlight? HIIT programmes in women significantly decrease body weight and total and abdominal FM. Their effects are more evident in pre- than in postmenopausal women. Cycling HIIT seems more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions a week should be promoted.

ABSTRACT

High-intensity interval training (HIIT) is a stimulating modality for reducing body weight and adipose tissue. The purpose of this meta-analysis was to assess the efficacy of HIIT in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. A structured electronic search was performed to find all publications relevant to our review. Stratified analyses were made of hormonal status (pre- vs. postmenopausal state), weight, HIIT modalities (cycling vs. running), programme duration (< or ≥8 weeks) and the methods used to measure body composition (dual-energy X-ray absorptiometry vs. computed tomography, Magnetic Resonance Imaging and others). A total of 38 studies involving 959 subjects were included. Our meta-analysis showed that overall HIIT programmes significantly decrease weight, total and abdominal FM in women. Both normal weight and overweight/obese women lost total FM after HIIT protocols whereas HIIT was only effective in decreasing abdominal FM in women with excess adiposity. When pre- and postmenopausal women were considered separately, the effect of HIIT on weight, total and abdominal FM were only significant before menopause. Cycling HIIT seemed more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions were more efficient. HIIT is a successful strategy to lose weight and FM in normal weight and overweight/obese women. However, further studies are still needed to draw meaningful conclusions about the real effectiveness of HIIT protocols in postmenopausal women.