A 4-week caloric restriction with high volume resistance-training and high-protein diet does not increase fat-free mass sparing but increases strength
摘要
Athletes employ weight loss protocols to lower fat mass (FM) and maintain fat-free mass (FFM) for performance purposes. High volume resistance-training (HVRT) has been associated with greater increases in FFM than low volume resistance-training (LVRT). However, less is known about the effects of HVRT under caloric restriction (CR). Therefore, it remains unclear whether HVRT could elicit greater retention of FFM and improvements in strength during CR.
ObjectivesDetermine the effects of HVRT and high protein intake on FFM and strength in resistance- trained individuals after a 40% CR.
MethodsSixteen resistance-trained individuals underwent a high-protein (2.3 g/kg body mass (BM)), 4- week 40% CR with a 5-day/week resistance-training intervention. Participants were randomly assigned to LVRT (12 sets/muscle group/week) or HVRT (30 sets/muscle group/week). Pre-post intervention testing included dual energy x-ray absorptiometry, indirect calorimetry, dietary records, resistance-training records, 5RM strength testing, and nitrogen balance.
ResultsSignificant reductions in BM (Δ –4.2 ± 0.5 kg, p < 0.001), FM (Δ –3.7 ± 0.4 kg, p < 0.001), and %FM (Δ –3.5 ± 0.4%, p < 0.001) were observed, but changes were not different between groups. No intervention or group by intervention effects were noted for FFM. HVRT produced greater increases for 5RM testing for chest press (p = 0.005), right leg press (p = 0.003), and left leg press (p < 0.001).
ConclusionHVRT does not seem to further enhance FFM retention during a 40% CR. Albeit, greater increases in strength were noted in HVRT, but mechanisms underlying such improvements remain to be investigated.