Changes in body composition after 6 weeks of two velocity based resistance training: 20% vs 40% of velocity loss

  1. Costilla M. 2
  2. Marín-Galindo A. 12
  3. Corral-Román J 12
  4. Muñoz-López A. 4
  5. Sánchez-Sixto A. 5
  6. Casals C 12
  7. Ponce-González J.G. 12
  8. Sañudo B. 3
  1. 1 MOVE-IT Research group and Department of Physical Education, Faculty of Education Sciences, University of Cádiz, Cádiz, Spain
  2. 2 Biomedical Research and Innovation Institute of Cádiz (INiBICA) Research Unit, Puerta del Mar University Hospital, University of Cádiz, Spain
  3. 3 Department of Physical Education and Sports, University of Seville, Seville, Spain
  4. 4 Department of Human Motor Skills and Sport Performance, University of Seville, Seville, Spain
  5. 5 Centro de Estudios Universitarios Cardenal Spínola, CEU, Seville, Spain
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Actas:
XII International Symposium in Strength Training

Editorial: Universidad Politécnica de Madrid

ISBN: 978-84-09-16216-1

Año de publicación: 2019

Páginas: 151-152

Tipo: Aportación congreso

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Resumen

Two resistance training programs showed that 40% velocity loss-based (40VL) training (̴40% more repetitions) increasedcross-sectional area in Vastus Lateralis and Vastus Intermedius compared with a 20% velocity loss-based (20VL) training(1). A greater training volume in 40VL promotes hypertrophy adaptations which are enhancing with a dose-response relationship(2). We aimed to study the changes in body composition (fat and lean mass) after performing a RTprogram at 40VL or 20VL. METHODS 26 young men (21.8±2.3 yrs) were randomly recruited to three groups: 20VL (n=9), 40VL (n=8) and Control (n=9). Participants performed 8-week RT-program using barbell back squat exercise controlling mean propulsive velocity. Body mass (BM), lean mass (LM) and fat mass (FM) were measured using a multifrequency bioimpedance previously validated (TANITAMC780MA) following these considerations: i) to refrain from vigorous exercise 24h before, ii) to avoid alcoholic or energy drinks 24h before, iii) to be in a fasting state for 8h. Repeated-measures-ANOVA and Bonferroni post hoc comparisons were performed. RESULTS For 20VL, no differences were found before and after the RT-program in BM (69, 69.6±3.7 vs. 69.3±3.8kg), LM (55.7±2.1 vs. 56.1±2.1kg), and legs-LM (19.5±0.7 vs. 19.8±0.7kg); however, FM and legs-FM were significantly reduced after the RT-program (10.9±2.0 vs. 10.18±2.1kg, p<0.01; and 3.3±0.6 VS 3.1±0.6kg, p<0.05; respectively). For 40VL, no differences were found in any analysed variables (BM: 74.7±3.9 vs. 75.1±4.0kg, LM: 58.3±6.6 vs. 58.8±6.0kg, legs-LM: 20.6±0.7 vs. 20.7±0.7kg, FM: 13.3±2.2 vs. 13.2±2.2kg, legs-FM: 3.9±1.2 vs. 3.76±1.3kg); similarly to the Control group (BM: 78.0±3.7 vs. 77.3±3.8kg, LM: 61.0±8.0 vs. 60.5±8.0kg, legs-LM: 21.4±0.7 vs. 21.2±0.7kg, FM: 13.7±2.0 vs. 13.6±2.1kg, legs-FM: 4.1±2.8 vs. 4.1±2.9kg). No differences were found between groups before and after RT-program. DISCUSSION Our results showed a reduction of FM and legs-FM after an 8-week RT-program only in 20VL, without differences in 40VL and controls. This could be explained by two factors: i) insufficient energy balance in 40VL, despite participants were asked to avoid changes in nutritional habits, and ii) lower physical activity-ratio based in a high residual-fatigue of 40VL.