The Effects of Chocolate Milk on Recovery From Exercise

Abstract

Introduction: Exercise is commonly followed by fatigue which an athlete usually tries to minimize with the intake of protein supplements and high protein diets. The fatigue felt by the athlete can have an effect on his or her ability to perform at the same level while focusing on similar muscle groups. Increasing protein intake speeds up the recovery process of the muscles used during exercise, and measurements such as maximal oxygen consumption (VO2max) can be used to determine whether or not the athlete can perform exercise at the same level of intensity while targeting the same muscle groups. The VO2max is the maximum capacity of the body to transport and utilize oxygen during incremental exercise. According to research, chocolate milk has a 4:1 carbohydrate to protein ratio that is believed to positively influence recovery.

Purpose: The purpose of this study was to determine if chocolate milk helps in the recovery process after a bout of high intensity exercise is performed.

Methods: Initially, ten university males were chosen to be a part of this study, which was later cut to eight total subjects. Following VO2max testing the groups were divided into treatment (chocolate milk; 21.5± 1 yrs) and placebo groups (Propel; 22 ± 0.82 yrs). The beverages were given post exercise. Each subject performed a graded exercise test on the treadmill with increasing speed and elevation until exhaustion. During each test heart rate (HR), rate of perceived exertion (RPE), and VO2max were recorded, as well as time of exercise.

Results: The calculated time of exercise following supplementation was (CM: 12:26 ± 0:53 min; P: 10:45 ± 0:07 min); heart rate max (CM: 191.5 ± 12.4 bpm; P: 191 ± 10.89 bpm); RPE max (CM: 17.5 ± 1.29; P: 17 ± 2.45); and relative VO2max (CM: 46.83 ± 3.79 ml/kg/min; P: 41.93 ± 7.6 ml/kg/min). There were not any significant differences between the chocolate milk group and the propel group (p = 0.1).

Conclusion: The results of this study indicate that there is not a significant difference among the two groups, when comparing them to the p value (p = 0.1). The little differences observed, such as time lasted (p = 0.12) may have been due to different levels of fitness among the subjects, but it wasn’t enough to cause a significant difference. A questionnaire was given to each subject prior to exercise, and each runner said that they felt no fatigue before performing the test. In future studies, it may be beneficial to conduct a different test, such as a bicep resistance training test in order to potentially yield more fatigue among the muscles, and therefore truly test the effect of a protein shake on muscle recovery.