•Individual XRM-velocity relationships provided higher goodness of fit compared to general relationships on both testing sessions.•The goodness of fit of individual XRM-velocity relationships was not ...affected by sex, training status and history or personality traits.•Individual, but not general XRM-velocity relationships established in the first testing session provided acceptable predictions of XRM in the second testing session, on average.•Prediction accuracy of individual XRM-velocity relationships was not affected by sex, training status and history, or personality traits.
The aim of this study was to examine the goodness of fit and prediction accuracy of general and individual relationships between the maximum number of repetitions completed in a set (XRM) and the fastest repetition in the set (XRM-velocity relationship) in the free-weight back squat exercise. The effects of sex, training status and history, as well as personality traits, on the goodness of fit and the accuracy of these relationships were also investigated. Forty-six resistance-trained people (15 females and 31 males) performed a one-repetition maximum (1RM) test, and two repetitions to failure (RTF) tests, 72 h apart. RTF tests were performed with 70, 80, and 90% of 1RM with 10 min of inter-set rest. A greater goodness of fit was found for individual XRM-velocity relationships (R2 = 0.98; residual standard error RSE = 1.01–1.15) compared to general XRM-velocity relationships (R2 = 0.45–0.49; RSE = 3.44–3.66). Individual, but not general XRM-velocity relationships established in the first testing session yielded acceptable prediction accuracy (mean error = 1.96 vs 2.81 repetitions) of XRM in the subsequent testing session. Sex, training status and history, and personality traits did not affect the goodness of fit of general and individual XRM-velocity relationships or their prediction accuracy, suggesting the potential generalisability of those findings among resistance-trained populations. Therefore, individual XRM-velocity relationships can be used to prescribe loads matching an intended XRM by recording only the fastest velocity of the set with a given load and predicting, with reasonable accuracy, the XRM for the individual.
We performed a systematic review, meta-analysis and meta-regression to determine if dietary protein supplementation augments resistance exercise training (RET)-induced gains in muscle mass and ...strength.
A systematic search of Medline, Embase, CINAHL and SportDiscus.
Only randomised controlled trials with RET ≥6 weeks in duration and dietary protein supplementation.
Random-effects meta-analyses and meta-regressions with four a priori determined covariates. Two-phase break point analysis was used to determine the relationship between total protein intake and changes in fat-free mass (FFM).
Data from 49 studies with 1863 participants showed that dietary protein supplementation significantly (all p<0.05) increased changes (means (95% CI)) in: strength-one-repetition-maximum (2.49 kg (0.64, 4.33)), FFM (0.30 kg (0.09, 0.52)) and muscle size-muscle fibre cross-sectional area (CSA; 310 µm
(51, 570)) and mid-femur CSA (7.2 mm
(0.20, 14.30)) during periods of prolonged RET. The impact of protein supplementation on gains in FFM was reduced with increasing age (-0.01 kg (-0.02,-0.00), p=0.002) and was more effective in resistance-trained individuals (0.75 kg (0.09, 1.40), p=0.03). Protein supplementation beyond total protein intakes of 1.62 g/kg/day resulted in no further RET-induced gains in FFM.
Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults. Increasing age reduces and training experience increases the efficacy of protein supplementation during RET. With protein supplementation, protein intakes at amounts greater than ~1.6 g/kg/day do not further contribute RET-induced gains in FFM.
The alteration of individual sets during resistance training (RT) is often used to allow for greater velocity and power outputs, reduce metabolite accumulation such as lactate and also reduce ...perceived exertion which can ultimately affect the resultant training adaptations. However, there are inconsistencies in the current body of evidence regarding the magnitude of the effects of alternative set structures (i.e., cluster sets and rest redistribution) on these acute mechanical, metabolic, and perceptual responses during and after RT.
This study aimed to systematically review and meta-analyse current evidence on the differences between traditional and alternative (cluster and rest redistribution) set structures on acute mechanical, metabolic, and perceptual responses during and after RT, and to discuss potential reasons for the disparities noted in the literature.
The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and five databases were searched until June 2019. Studies were included when they were written in English and compared at least one acute mechanical, metabolic, or perceptual response between traditional, cluster or traditional and rest redistribution set structures in healthy adults. Random-effects meta-analyses and meta-regressions were performed where possible.
Thirty-two studies were included. Pooled results revealed that alternative set structures allowed for greater absolute mean standardized mean difference (SMD) = 0.60 and peak velocity (SMD = 0.41), and mean (SMD = 0.33) and peak power (SMD = 0.38) during RT. In addition, alternative set structures were also highly effective at mitigating a decline in velocity and power variables during (SMD = 0.83-1.97) and after RT (SMD = 0.58) as well as reducing lactate accumulation (SMD = 1.61) and perceived exertion (SMD = 0.81). These effects of alternative set structures on velocity and power decline and maintenance during RT were considerably larger than for absolute velocity and power variables. Sub-group analyses controlling for each alternative set structure independently showed that cluster sets were generally more effective than rest redistribution in alleviating mechanical, metabolic, and perceptual markers of fatigue.
Alternative set structures can reduce mechanical fatigue, perceptual exertion, and metabolic stress during and after RT. However, fundamental differences in the amount of total rest time results in cluster sets generally being more effective than rest redistribution in alleviating fatigue-induced changes during RT, which highlights the importance of classifying them independently in research and in practice. Additionally, absolute values (i.e., mean session velocity or power), as well as decline and maintenance of the mechanical outcomes during RT, and residual mechanical fatigue after RT, are all affected differently by alternative set structures, suggesting that these variables may provide distinct information that can inform future training decisions.
The original protocol was prospectively registered (CRD42019138954) with the PROSPERO (International Prospective Register of Systematic Reviews).
•Carbohydrate (CHO)-loading protocols are commonly implemented by bodybuilders.•Four males completed this double-blind randomized crossover trial.•Participants consumed 9 g/kg CHO or placebo drinks ...following 3 days of 1–2 g/kg CHO.•Changes may not be large enough to exceed measurement error and daily variation.•Coaches and competitors should test protocols well in advance of competition.
To acutely enhance muscle size and definition, carbohydrate (CHO)-loading protocols are commonly implemented by bodybuilders in the week before competition. This study sought to evaluate the effects of a bodybuilding CHO-loading protocol on anthropometry. Four dieting males engaging in resistance training (RT) with very low body fat participated in this randomized crossover trial. Each experimental period consisted of data collection on days one, four, and five corresponding to baseline, postdepletion, and postloading phases, respectively. During depletion, a standardized RT regimen and diet was followed. This diet was maintained on day 4 with the addition of placebo (PLA) or CHO drinks which contained 9 g/kg BM CHO for postloading data collection on day 5. Body mass (BM), skinfold thickness (SF), and ultrasound muscle thickness (MT) were obtained with descriptive data at both group and individual level calculated. From baseline, BM, SF, and MT mostly decreased in both conditions following depletion. All outcomes then increased from postdepletion following CHO-loading (BM: +0.8%, SF: +1.1%, MT: +2.9%) but not with PLA. Comparing to baseline, postloading changes were greater with CHO (BM: +0.3%, SF: -2.3%, MT: +2.1%) than PLA (BM: -0.9%, SF: -0.5%, MT: -0.8%). Individual differences in response to each phase were also observed. Group level changes seemingly favor CHO-loading; however, it is difficult to judge whether these changes are practically meaningful as they may not be large enough to exceed measurement error and daily biological fluctuations. Before implementation, coaches and competitors should consider individualizing protocols through precompetition testing and visually assessing changes in physique.
Is bodybuilding a sport? Kind, Adrian; Helms, Eric R.
Journal of the philosophy of sport,
05/2023, Letnik:
50, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Since its beginnings, modern bodybuilding has been accompanied by the background issue of whether it should be considered a sport. The problem, culminating in its provisional acceptance as a sport by ...the International Olympic Committee, was later retracted. The uncertainty of whether bodybuilding is a sport or not seems to linger. Addressing this issue, Aranyosi (2018) provided an account to determine the status of bodybuilding as a sport that arrives at the negative answer: bodybuilding is not a sport but rather a form of artistic presentation. In this paper, we disagree with Aranyosi. We argue that by the standards he presents in his first argument, bodybuilding should be considered a sport. Further, we argue that his alternative approach on how to evaluate a discipline as more sport- or art-like on a spectrum, is not a valid basis to make such a judgment regarding bodybuilding. Further, even if his spectrum was modified to enable such a judgment, again it would result in bodybuilding being evaluated as a sport. Therefore, we conclude that everyone who accepts Aranyosi´s (or any less restrictive) requirements to decide whether bodybuilding is a sport, has to consider bodybuilding as a sport or refrain from making claims about its status.
Purpose
The aim of this study was to examine the goodness of fit, prediction accuracy, and stability of general and individual relationships between velocity loss and the percentage of completed ...repetitions out of maximum possible (VL-%
repetitions
) in the free-weight back squat exercise. The effects of sex, training status and history, as well as personality traits, on the goodness of fit and the accuracy of these relationships were also investigated.
Methods
Forty-six resistance-trained people (15 females and 31 males) performed a one-repetition maximum (1RM) test, and two repetitions to failure (RTF) tests, 72 h apart. RTF tests were performed with 70, 80, and 90% of 1RM with 10 min inter-set rest.
Results
The findings question the utility of using general and individual VL-%
repetitions
relationships to prescribe training volume with free-weight back squats as (1) the agreement in the %
repetitions
completed until reaching a given velocity loss threshold across two consecutive testing sessions was unacceptable, regardless of the load used; and (2) the ability of general and individual VL-%
repetitions
relationships to predict %
repetitions
in a subsequent testing session were poor (absolute errors > 10%). Sex, training status and history, and personality traits did not affect the goodness of fit of general and individual VL-%
repetitions
relationships or their prediction accuracy, suggesting potential generalisability of those findings among resistance-trained populations.
Conclusions
VL-%
repetitions
relationships do not seem to provide any additional benefits compared to costless, traditional methods and hence should not be used for monitoring and prescribing resistance training with a free-weight back squat exercise.
Athletes undergoing energy restriction for weight/fat reduction sometimes apply 'diet breaks' involving increased energy intake, but there is little empirical evidence of effects on outcomes. ...Twenty-six resistance-trained athletes (11/26 or 42% female) who had completed 12 weeks of intermittent energy restriction participated in this study. Participants had a mean (SD) age of 29.3 (6.4) years, a weight of 72.7 (15.9) kg, and a body fat percentage of 21.3 (7.5) %. During the 1-week diet break, energy intake was increased (by means of increased carbohydrate intake) to predicted weight maintenance requirements. While the 1-week diet break had no significant effect on fat mass, it led to small but significant increases in mean body weight (0.6 kg, P<0.001), fat-free mass (0.7 kg, P<0.001) and in resting energy expenditure, from a mean (and 95% confidence interval) of 7000 (6420 to 7580) kJ/day to 7200 (6620 to 7780) kJ/day (P = 0.026). Overall, muscle endurance in the legs (but not arms) improved after the diet break, including significant increases in the work completed by the quadriceps and hamstrings in a maximum-effort 25-repetition set, with values increasing from 2530 (2170 to 2890) J to 2660 (2310 to 3010) J (P = 0.018) and from 1280 (1130 to 1430) J to 1380 (1220 to 1540) J (P = 0.018) following the diet break, respectively. However, muscle strength did not change. Participants reported significantly lower sensations of hunger (P = 0.017), prospective consumption (P = 0.020) and irritability (P = 0.041) after the diet break, and significantly higher sensations of fullness (P = 0.002), satisfaction (P = 0.002), and alertness (P = 0.003). In summary, a 1-week diet break improved muscle endurance in the legs and increased mental alertness, and reduced appetite and irritability. With this considered, it may be wise for athletes to coordinate diet breaks with training sessions that require muscle endurance of the legs and/or mental focus, as well as in the latter parts of a weight loss phase when increases in appetite might threaten dietary adherence. Trial registration: Australian New Zealand Clinical Trials Registry Reference Number: ACTRN12618000638235 anzctr.org.au.
The popularity of natural bodybuilding is increasing; however, evidence-based recommendations for it are lacking. This paper reviewed the scientific literature relevant to competition preparation on ...nutrition and supplementation, resulting in the following recommendations. Caloric intake should be set at a level that results in bodyweight losses of approximately 0.5 to 1%/wk to maximize muscle retention. Within this caloric intake, most but not all bodybuilders will respond best to consuming 2.3-3.1 g/kg of lean body mass per day of protein, 15-30% of calories from fat, and the reminder of calories from carbohydrate. Eating three to six meals per day with a meal containing 0.4-0.5 g/kg bodyweight of protein prior and subsequent to resistance training likely maximizes any theoretical benefits of nutrient timing and frequency. However, alterations in nutrient timing and frequency appear to have little effect on fat loss or lean mass retention. Among popular supplements, creatine monohydrate, caffeine and beta-alanine appear to have beneficial effects relevant to contest preparation, however others do not or warrant further study. The practice of dehydration and electrolyte manipulation in the final days and hours prior to competition can be dangerous, and may not improve appearance. Increasing carbohydrate intake at the end of preparation has a theoretical rationale to improve appearance, however it is understudied. Thus, if carbohydrate loading is pursued it should be practiced prior to competition and its benefit assessed individually. Finally, competitors should be aware of the increased risk of developing eating and body image disorders in aesthetic sport and therefore should have access to the appropriate mental health professionals.
Background and Objective
This systematic review with meta-analysis investigated the influence of resistance training proximity-to-failure on muscle hypertrophy.
Methods
Literature searches in the ...PubMed, SCOPUS and SPORTDiscus databases identified a total of 15 studies that measured muscle hypertrophy (in healthy adults of any age and resistance training experience) and compared resistance training performed to: (A) momentary muscular failure versus non-failure; (B) set failure (defined as anything other than momentary muscular failure) versus non-failure; or (C) different velocity loss thresholds.
Results
There was a trivial advantage for resistance training performed to set failure versus non-failure for muscle hypertrophy in studies applying any definition of set failure effect size=0.19 (95% confidence interval 0.00, 0.37),
p
=0.045, with no moderating effect of volume load (
p
=0.884) or relative load (
p
=0.525). Given the variability in set failure definitions applied across studies, sub-group analyses were conducted and found no advantage for either resistance training performed to momentary muscular failure versus non-failure for muscle hypertrophy effect size=0.12 (95% confidence interval −0.13, 0.37),
p
=0.343, or for resistance training performed to high (>25%) versus moderate (20–25%) velocity loss thresholds effect size=0.08 (95% confidence interval −0.16, 0.32),
p
=0.529.
Conclusion
Overall, our main findings suggest that (i) there is no evidence to support that resistance training performed to momentary muscular failure is superior to non-failure resistance training for muscle hypertrophy and (ii) higher velocity loss thresholds, and theoretically closer proximities-to-failure do not always elicit greater muscle hypertrophy. As such, these results provide evidence for a potential non-linear relationship between proximity-to-failure and muscle hypertrophy.