PURPOSE: The purpose of this study was to determine the effectiveness of chocolate milk (CM) as a post-exercise recovery beverage during intensified training in competitive soccer players.
METHODS: Thirteen collegiate soccer players (184±7 cm, 79±10 kg) completed two intervention periods, each consisting of one week of 'normal' training followed by four days of intensified-training (IT). Immediately following each day of IT, subjects received either a high-carbohydrate (CHO: 1.77g CHO· kgBW-1; 0.03g Fat· kgBW-1) or CM (1.2g CHO· kgBW-1; 0.4g Pro· kgBW-1; 0.1g Fat· kgBW-1) recovery beverage. Treatment beverages were isocaloric, and delivered in a randomly-counterbalanced double-blind protocol. Serum creatine kinase (CK) and myoglobin (Mb) levels, muscle soreness, mental and physical fatigue, peak isometric force of the quadriceps (MVC), and leg-extension repetitions at 70% 1-RM (Reps) were obtained prior to IT, and following 2- and 4-days of IT. Soccer-specific performance tests (t-drill, vertical jump and 1.5 mile run speed) were performed within the training sessions.
RESULTS: Average daily training times (85.3±5.0; 95.3±7.9 min) and HR (141.8±12.1; 145±10.9 bpm) increased significantly (p<0.05) between baseline and IT periods, with no differences between treatment periods. Soreness, CK, Mb, MVC and Reps were all significantly altered over time during the IT period. No significant treatment* time interactions were observed. However, serum CK levels during the CM treatment were significantly lower (p<0.05) than CHO following two (343.5±199.8; 449.9±364.8 U/L) and four (316.9±188.3; 431.6±310.8 U/L) days of IT. Mean changes in isometric MVC values for CM (+52.7 N) tended to be greater than those for CHO (+24.6 N), although this was not statistically different between treatments. No significant differences in soccer-specific performance tests were observed between treatment beverage.s
CONCLUSIONS: Post-exercise CM consumption provided equal or possibly superior muscle recovery responses to an isocaloric, high-carbohydrate recovery beverage following a four-day period of intensified soccer training. Performance in soccer-specific field tests were similar between beverages.