Association Between Foundation Strength and Weightlifting Exercises in Highly Trained Weightlifters: Support for a General Strength Component

ABSTRACT

Zecchin, A, Puggina, EF, Hortobágyi, T, and Granacher, U. Association between foundation strength and weightlifting exercises in highly trained weightlifters: support for a general strength component. J Strength Cond Res 37(7): 1375-1381, 2023-In addition to specific weightlifting exercises (i.e., clean and jerk and snatch), foundation strength exercises (i.e., overhead press, front squat, and deadlift) constitute an integral part of the weightlifters' training regime. The unexamined concept behind this training plan is that foundation strength exercises are associated with clean and jerk and snatch performance, implying the existence of a general strength component. We thus determined the relationship between performance in foundation strength exercises (overhead press, front squat, and deadlift) and weightlifting exercises (clean and jerk and snatch) in weightlifters. Well-trained weightlifters ( N = 19, age: 26.8 ± 4.4 years; body mass index: 27.6 ± 2.3 kg·m -2 ; and training history: 4.6 ± 0.8 years) performed 1 repetition maximum tests (1RM) in foundation strength and weightlifting exercises, over 14 days, in a randomized order. We observed significant correlations in 1RM performance between the overhead press and snatch ( r = 0.69), front squat and snatch ( r = 0.73), overhead press and clean and jerk ( r = 0.67), and front squat and clean and jerk ( r = 0.72, all r values: p < 0.01). No significant correlations were found for 1RM performance between the snatch and deadlift or between the clean and jerk and deadlift ( r- range: 0.20-0.58; p > 0.05). Stepwise linear regression revealed that 1RM performance in the overhead press and front squat explained 62% of the variance in snatch 1RM performance ( F = 5.51; p < 0.04). Overhead press and front squat 1RM performance explained 59% of the variance in the clean and jerk 1RM performance ( F = 5.14; p < 0.04). Our results demonstrate the existence of a general strength component between selected foundation strength exercises and weightlifting performance. However, the use of the front squat and overhead press to increase 1RM performance in weightlifting exercises needs to be determined in future research using a different methodological approach (i.e., longitudinal protocols), given that the observed correlations do not necessarily imply causation.

Two days of simulated CrossFit competition affect autonomic nervous system but not anaerobic power or fatigue

BACKGROUND

We examined changes in autonomic nervous system function, anaerobic power, and fatigue over two days of simulated CrossFit competition in CrossFit athletes. In addition, we determined the relationship between these internal training load variables and variables characterizing two weeks of tapering preceding the competition.

METHODS

In total, 21 participants (Intervention group, n=10, INT; Control group, n=11, CON) completed the assessments. INT performed the assessments at baseline (pre-Day 1), during the competition (post-Day 1 and pre-Day 2), and after the competition (post-Day 2), while CON performed only the baseline assessments.

RESULTS

Autonomic nervous system function, anaerobic power, and fatigue did not differ between the beginning of Day 1 and Day 2. Autonomic nervous system function was impaired at the end of each day. Anaerobic power and fatigue did not change during either day.

CONCLUSIONS

Finally, the two training weeks preceding the two days of simulated competition were related to anaerobic power but not autonomic nervous system function or fatigue. CrossFit coaches and athletes should be aware of the limited effects of step taper on heart rate variability and fatigue.

High plasma soluble levels of the immune checkpoint HLA-G molecule among bodybuilders

Introduction

Studies report that intense physical activity influences the down-regulation of immune function in athletes as well as the interaction between adipose tissue and the immune system.

Aim

This study aimed to compare the plasma soluble levels of the immune checkpoint HLA-G (sHLA-G) molecule with the fat mass and muscle mass index among 77 bodybuilders and 64 controls.

Results

The comparisons of the percentage of body fat (%BF) revealed that the groups of male and female bodybuilders showed a statistically significant reduction in the percentage of body fat when compared to their control group, (P <0.0001, for both comparisons). Regarding sHLA-G levels, the comparisons showed that the group of male bodybuilders had significantly higher sHLA-G levels compared to the group of female bodybuilders (P = 0.0011).

Conclusion

Our results showed that in bodybuilders with less body fat, the systemic levels of soluble HLA-G, an immunological molecule with recognized immunosuppressive function, are significantly higher and suggest that this immune mechanism may corroborate the immunosuppressive state in athletes undergoing intense and prolonged physical training.

Validity and reliability of a 6-a-side small-sided game as an indicator of match-related physical performance in elite youth Brazilian soccer players

The aims of this study were: (i) to compare the external and internal load during a 6-a-side small-sided game (6v6-SSG) according to age-group; (ii) to relate these parameters between the 6v6-SSG and official matches; and (iii) to test the reliability of the 6v6-SSG. A total of 51 Brazilian youth soccer players participated in this study (U11 [n = 16]; U13 [n = 10]; U15 [n = 9]; U17 [n = 8]; U20 [n = 8]). Three experiments were conducted. Experiment A: fifty-one U11 to U20 players were submitted to 6v6-SSGs (n = 10 games; two for each age-group). Experiment B: thirty-two players were randomized to also play official matches (n = 6 matches). Experiment C: thirty-five youth players played the 6v6-SSG twice for test and retest reliability analysis. External load was obtained using Global Positioning Systems and the internal load parameter was calculated through mean heart rate. Statistical approaches showed progressive increases in all parameters according to categories (U11< U13< U15< U17< U20; p < 0.05; ES = 0.42-23.68). Even controlling for chronological age, all parameters showed likely to almost certain correlations between 6v6-SSG and official matches (r = 0.25-0.92). Collectively, the proposed protocol indicates good reliability (CV% = 2.0-12.6; TE% = 2.3-2.7%; ICC = 0.78-0.90). This research suggests that the 6v6-SSG is an alternative tool to indicate match-related physical performance in youth soccer players.

Acute Effects of Active, Ballistic, Passive, and Proprioceptive Neuromuscular Facilitation Stretching on Sprint and Vertical Jump Performance in Trained Young Soccer Players

Oliveira, LP, Vieira, LHP, Aquino, R, Manechini, JPV, Santiago, PRP, and Puggina, EF. Acute effects of active, ballistic, passive, and proprioceptive neuromuscular facilitation stretching on sprint and vertical jump performance in trained young soccer players. J Strength Cond Res 32(8): 2199-2208, 2018-The aim of this study was to compare the acute effects of active (AC), ballistic (BA), passive (PA), and proprioceptive neuromuscular facilitation (PNF) stretching methods on performance in vertical jumping, sit and reach, and sprinting in young soccer players. Twelve trained soccer players (17.67 ± 0.87 years) participated in the study. The jump height (H), peak power (PP), and relative power (RP) in the squat jump (SJ) and countermovement jump (CMJ), the range of motion (ROM), the rating of perceived exertion (RPE), and time (seconds) in 10-20-30-m sprints were evaluated. Significant differences (p < 0.05) in H were found in the comparisons between the PA and control (CO) condition for the SJ. For the CMJ, differences in H were observed between the PA and CO, and PNF with CO and BA, and in the PP between the PNF and CO, AC, and BA, as well as in the RP between the PNF and BA. Significant increases in ROM were found in the AC, BA, PA, and PNF compared with the CO. In relation to RPE, higher scores were reported in the PA and PNF conditions compared with the AC and BA. No significant differences were found in 10-20-30-m sprints. Therefore, the AC and BA methods can be used before vertical jump and sprint activities, with the aim of increasing flexibility. However, the PA and PNF methods should be avoided because of subsequent negative effects on vertical jump performance.

Multivariate Profiles of Selected versus Non-Selected Elite Youth Brazilian Soccer Players

This study determined whether a multivariate profile more effectively discriminated selected than non-selected elite youth Brazilian soccer players. This examination was carried out on 66 youth soccer players (selected, n = 28, mean age 16.3 ± 0.1; non-selected, n = 38, mean age 16.7 ± 0.4) using objective instruments. Multivariate profiles were assessed through anthropometric characteristics, biological maturation, tactical-technical skills, and motor performance. The Student’s t-test identified that selected players exhibited significantly higher values for height (t = 2.331, p = 0.02), lean body mass (t = 2.441, p = 0.01), and maturity offset (t = 4.559, p < 0.001), as well as performed better in declarative tactical knowledge (t = 10.484, p < 0.001), shooting (t = 2.188, p = 0.03), dribbling (t = 5.914, p < 0.001), speed – 30 m (t = 8.304, p < 0.001), countermovement jump (t = 2.718, p = 0.008), and peak power tests (t = 2.454, p = 0.01). Forward stepwise discriminant function analysis showed that declarative tactical knowledge, running speed –30 m, maturity offset, dribbling, height, and peak power correctly classified 97% of the selected players. These findings may have implications for a highly efficient selection process with objective measures of youth players in soccer clubs.

Skill-related performance in soccer: a systematic review

The aim of the study was to evaluate and organize systematically the available literature on skill-related performance in young and adult male soccer players in an attempt to identify the most common topics, ascertain the weaknesses, and elucidate the main contributions of the scientific papers on this issue. A systematic review of the Institute for Scientific Information (ISI) Web of Knowledge database was performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. The keywords ‘football’ and ‘soccer’ were used, each associated with the following terms: ‘technical analysis,’ ‘technical performance,’ ‘technical activity,’ ‘technical skill,’ ‘technical demands,’ ‘technical profiles,’ ‘technical characteristics,’ ‘technical actions,’ ‘technical scores,’ ‘technical ability,’ ‘motor skills,’ and ‘skill acquisition’. From the 2830 papers, only 60 were reviewed, of which 75% had been published in years 2011-2015 and 53.3% concerned professional or seniors players (above the U-20 category). Out of the 41 papers that analysed the skill-related performance in the match, 48.8% evaluated the performance in small-sided and conditioned games. Among the 27 papers that used validated instruments, 88.9% assessed technical actions outside the match context (e.g. dribbling, shooting tests). Future research should pay attention to the definition and classification of the skill-related variables under investigation in match context and propose tests for measured skill-related performance in soccer, considering that the representativeness task design allies the players’ possibilities of action to the situation of the match.

Serum IGF-I, IGFBP-3 and ALS concentrations and physical performance in young swimmers during a training season

INTRODUCTION

The GH/IGF-I axis is a system of growth mediators, receptors, and binding proteins that regulate somatic and tissue growth; and it has been shown that exercise programs are related to the anabolic function of this axis.

OBJECTIVE

The aim of this study was to analyse the changes of serum IGF-I concentration and that of its binding proteins IGFBP-3 and ALS in adolescent swimmers at different stages of a training season, and compare them with physical performance parameters and body composition of the athletes.

MATERIAL AND METHODS

Nine male athletes, aged 16 to 19years and who trained regularly throughout the season, were included in this study. Serum IGF-I, IGFBP-3, and ALS concentrations were recorded before and after (pre×post) standardized training sessions during the different stages of a training season (extensive×intensive×tapering). Endurance in freestyle, anaerobic fitness in tied swimming (Peak Force and Average Force), body mass, fat percentage, and lean body mass were also analysed at the different stages of training in order to compare the changes of the IGF-I/IGFBP/ALS system with the physical performance and body composition of the athletes. Variations in the IGF-I/IGFBP-3-ALS system before and after a standardized training session, and at the different stages of training were analysed by the Wilcoxon and Friedman non-parametric tests, respectively. Significance was considered at 5%.

RESULTS

The results from this study demonstrate that IGF-I is sensitive to the acute and chronic effects of training, exhibiting biphasic behaviour throughout the season. The catabolic phase was characterized by a reduction in serum IGF-I concentrations during the intensive stage (∆_IGF-I: - 43.33±47.32ng/ml; P<0.05) while the anabolic phase was marked by similar basal concentrations at the different stages of training and an increase in post-training serum IGF-I concentrations during the tapering stage (320±40; 298±36 and 359±94ng/ml; P<0.05). IGFBP-3 was only sensitive to the chronic effects of training, with a reduction in post-training serum concentrations during the intensive stage and an increase during the tapering stage (4.7±0.7, 4.6±0.4 and 5.0±0.7mg/l; P<0.05). No significant difference (P>0.05) was observed in pre- or post-training IGFBP-3 concentrations (∆_IGFBP-3) at the different stages. ALS concentrations remained unchanged throughout the season, demonstrating that in adolescent athletes they are unaffected by the acute or chronic effects of swimming. Peak Force (25.0±6.3, 24.2±5.7 and 28.5±6.5N; P<0.05) and Average Force (10.3±3.6, 8.8±1.8 and 14.7±1.8N; P<0.05) followed IGF-I and IGFBP-3 variations, with a decrease during the intensive stage and a significant (P<0.05) increase during the tapering stage. The body composition and cardiorespiratory condition of the swimmers did not vary significantly throughout the season, exhibiting behaviour independent of IGF-I or IGFBP-3.

CONCLUSION

Serum IGF-I and IGFPB-3 concentrations have proven to be sensitive markers of training status and, thus, may be used as guides for coaches and athletes in the challenging task of modulating training intensity in young athletes.

Periodization Training Focused on Technical-Tactical Ability in Young Soccer Players Positively Affects Biochemical Markers and Game Performance

Aquino, RLQT, Cruz Gonçalves, LG, Palucci Vieira, LH, Oliveira, LP, Alves, GF, Pereira Santiago, PR, and Puggina, EF. Periodization training focused on technical-tactical ability in young soccer players positively affects biochemical markers and game performance. J Strength Cond Res 30(10): 2723-2732, 2016-The aim of this study was to investigate the effects of 22 weeks of periodized training, with an emphasis on technical-tactical ability, on indirect markers of muscle damage, and the on-field performance of young soccer players. Fifteen players (age 15.4 ± 0.2 years, height 172.8 ± 3.6 cm; body mass 61.9 ± 2.9 kg; % fat 11.7 ± 1.6; V[Combining Dot Above]O2max 48.67 ± 3.24 ml·kg·min) underwent 4 stages of evaluation: prepreparatory stage-T0; postpreparatory stage-T1; postcompetitive stage I-T2 and; postcompetitive stage II-T3. The plasmatic activity of creatine kinase (CK) and lactate dehydrogenase (LDH) were evaluated, as well as the on-field performance (movement patterns, tactical variables). Regarding the plasmatic activity of CK and LDH, there was a significant reduction (p ≤ 0.05) throughout the periodization training (T0: 350 U·L; T3: 150 U·L). Significant increases were observed (p ≤ 0.05) in the intensity of the game, high-intensity activities (HIA) (T0: 22%; T3: 27%), maximum speed (T0: 30 km·h; T3: 34 km·h) and tactical performance, team surface area (T0: 515 m; T3: 683 m), and spread (T0: 130 m; T3: 148 m). In addition, we found significant inverse correlations between the percentage variation of T0 to T3 in CK and LDH activities with percentage variation in high-intensity running (r = -0.85; p ≤ 0.05 and r = -0.84; p < 0.01, respectively) and HIA (r = -0.71 and r = -0.70; p ≤ 0.05, respectively) during the matches. We concluded that there was reduced activity in biochemical markers related to muscle damage, as well as increases in-game high-intensity performance and the tactical performance of the study participants. Furthermore, players who showed greater reduction in plasma activity of CK and LDH also obtained greater increases in-game high-intensity performance along the periodization. These results may contribute to the expansion and future consolidation of the knowledge of coaches and sport scientists to develop effective methodologies for training in soccer.

Biochemical, physical and tactical analysis of a simulated game in young soccer players

BACKGROUND

The objectives of this study were to describe and compare the displacement patterns and the tactical performance of the players in the first to the second game time and verify possible associations between indirect markers of muscle damage with displacement patterns in a simulated game played by young soccer players.

METHODS

Eighteen young soccer players were submitted to a simulated game and two blood collections, one before and another 30 minutes post-game to analyze the behavior of creatine kinase and lactate dehydrogenase enzymes. The patterns of displacement and tactics variables were obtained through functions developed in MATLAB environment (MathWorks, Inc., Natick, MA, USA).

RESULTS

It is observed a significant increase in average speed (P=0.05), number of sprints (P<0.001), the percentage the total distance covered at high intensity (P<0.001) and tactical variables (team surface area: P=0.002; spreading: P=0.001) in the second period of the simulated game. In addition, there was significant reduction in the percentage of the total distance at low intensity (P≤0.05) in the second period, and there was a strong association between the percentage of change delta of creatine kinase and lactate dehydrogenase with the displacement patterns in the simulated game.

CONCLUSIONS

The results show that indirect markers of muscle damage have great association with displacement patterns in game performed in training conditions for young soccer players, evidencing a need for reflection on the post-training recovery sessions strategies, contributing to better planning of sessions throughout the macrocycle.

Half-ironman induces changes in the kidney function of triathletes

Long duration exercise may lead to the occurrence of urine abnormalities. Aiming to investigate the effects of triathlon training and competition on the renal function, twelve male triathletes (32.60 ± 5.10 years, 175.04 ± 6.67m, 71.83 ± 7.42Kg) were studied during the 12-week training protocol and after a Half Ironman. Urine was collected in M-1 - beginning of the training season, M-2 - before the competition and M-3 - after the half ironman. Urine pH was measured using reagent strips, density with a refractometer, proteinuria by Bradford assay, creatinine with a colorimetric assay and blood cells by microscopy. Data were analyzed using Shapiro-Wilk test, One-Way ANOVA and Tukey-Kramer test (p < 0,05). Changes were found after the competition in the protein (M-1= 7.41 ± 2.48; M-2= 7.57 ± 3.74; M-3= 86.10 ± 76.21 mg/mL), creatinine (M-1= 157.66 ± 41.59; M-2= 177.68 ± 44.46; M-3= 316.46 ± 132.86 mg/mL), erythrocytes (M-1= 1060.00 ± 0.30; M-2= 1142.86 ± 377.96; M-3= 52555.56 ± 58.65 units/mL) and leucocytes (M-1= 2375.00 ± 744.02; M-2= 2090.00 ± 0.50; M-3= 5000.00 ± 2738.60 units/mL) excretion when compared to the other collection times. These effects are probably due to the exercise-induced modifications in the glomerular membrane and endocrine variables such as anti diuretic hormone, catecholamines and aldosterone.