Measurements were made before and after
(0, 24, 48 and 72 h) 120 minutes of treadmill walking at 6.5 km·h-1 (n = 10) on a level gradient (0%) carrying a 25 kg backpack with PD173074 supplier consumption of 250 ml (at 0 and 60 minutes) of a beverage containing either placebo (PLA – Black square), carbohydrate (6.4%) (CHO – Black triangle) or protein (7%) (PRO – Black circle) and twice daily (500 ml, morning and evening) for the 3 days after load carriage (n = 10). Symbols show difference from pre measurement for PLA (* P < 0.05), CHO († P < 0.05), PRO (# P < 0.05). Isokinetic Contractions of the Shoulder Extensors and Flexors There were no changes over time in any condition for the shoulder extensors (60°·s-1) (P = 0.124), shoulder extensors (180°·s-1) (P = 0.101), shoulder flexors (60°·s-1) (P = 0.094) or shoulder flexors (180°·s-1) (P = 0.078). Alvocidib Discussion The primary finding of the present study was that time course of recovery of neuromuscular function following prolonged load carriage (2 h, 25 kg) is improved with consumption of whey protein and carbohydrate beverages. After load carriage, isometric knee extension force recovered to pre-exercise values following 48 h recovery with carbohydrate and whey protein beverages compared to 72 h recovery
with a placebo. Interestingly, recovery of isokinetic peak torque was not improved by supplementation. buy RG7112 However, our experimental model had similar absolute loads during load carriage that may have resulted in large variation. It is possible that this large variation and our choice of analysing different recovery time points has masked, for example, potential improved effects of both supplements at 48 h for peak torque (60°·s-1) of the knee extensors (Figure 2) and the effect of whey protein at 48 h for peak torque (60°·s-1) of knee flexors (Figure 3). Reductions in torque in the present study are supported by data of Clarke et al. [1], which showed decreases in strength of knee and trunk extensors and flexors after a
12.1 km road march at 4 km·h-1 carrying a 27 kg load. Clarke et al. [1] observed larger Cobimetinib order decreases in knee extensor peak torque (6 vs. 8%) but smaller decreases in knee flexor peak torque (9 vs. 6%) with comparable reductions for changes in trunk extensor (12 vs. 11%) and flexor peak torque (10 vs. 11%). Whey protein intake during resistance training has been shown to improve muscle hypertrophy [7] and maintain a positive protein balance [15]. The effect of whey protein supplementation on recovery of muscle function after resistance or endurance exercise has received little attention. Buckley et al. [16] observed a ~23% decrease in isometric force of the knee extensors after 100 maximal eccentric contractions.