Chocolate milk is an effective recovery beverage following endurance exercise. The purpose of this study was to determine its efficacy, compared to a traditional sports drink, for recovery from intermittent, tournament-style exercise through measures of performance, perception, and rehydration. On 2 days, 7 days apart, female collegiate volleyball players completed an exercise session, rested for 2 h, and repeated the exercise. Participants consumed one of two recovery beverages in a randomized, counterbalanced crossover design. The volume of chocolate milk (CM) was calculated to meet the post-exercise carbohydrate recommendation (1.0 g carbohydrate·kg body weight−1·h−1), and the sports drink (carbohydrate-electrolyte beverage; CE) was matched for volume. The beverages had similar effects on performance and perception variables; no significant differences were noted between treatments. Total urine volume collected over the 2-h recovery period was significantly lower for CM than CE (CM: M = 217, SD = 115 ml vs. CE: M = 412, SD = 245 ml; Z = 2.60, p = .009; r = −.58), and when total fluid consumed during recovery was compared to urine output as a percent retained, a significant difference was seen between CM and CE (CM: 79.7% vs. CE: 61.4%; t = −3.34, p = .009; d = 1.06). Thus, it was concluded that chocolate milk is as effective as a traditional sports drink for females recovering from intermittent exercise with a short (2 h) recovery period, and that chocolate milk may be more beneficial than a sports drink for achieving rehydration post-exercise.
Kelsey Dow, Robert Pritchett, Karen Roemer and Kelly Pritchett
Kelly Pritchett, Robert C. Pritchett, Lauren Stark, Elizabeth Broad and Melissa LaCroix
Recent studies suggest that a substantial proportion of athletes with spinal cord injury have insufficient 25(OH) vitamin D (25(OH)D) status, which may be associated with decreased muscle strength. This study consisted of two parts: (a) to examine the effects of a 12- to 16-week vitamin D3 supplementation protocol on 25(OH)D concentration and (b) to determine whether subsequent 25(OH)D status impacts muscle performance in elite athletes with spinal cord injury. Thirty-four members (age: 33 ± 15 years, weight: 69.6 ± 28.2 kg, and height: 170.2 ± 25.4 cm) of the U.S. and Canadian Paralympic program participated in the study. 25(OH)D concentrations and performance measures (handgrip strength and 20-m wheelchair sprint) were assessed pre- and postsupplementation. Participants were assigned a vitamin D3 supplementation protocol based on initial 25(OH)D concentrations. Participants with deficient 25(OH)D status (<50 nmol/L) received 50,000 IU/week for 8 weeks, and participants with insufficient status (50–75 nmol/L) received 35,000 IU/week for 4 weeks, after which both received a maintenance dose of 15,000 IU/week. Participants with sufficient status (>75 nmol/L) received the maintenance dose of 15,000 IU/week. 25(OH)D concentrations increased significantly (p < .001; 66.3 ± 24.3 nmol/L and 111.3 ± 30.8 nmol/L pre- and postsupplementation, respectively). About 26% of athletes had sufficient 25(OH)D concentrations presupplementation, and 91% had sufficient concentrations postsupplementation. About 62% of participants improved handgrip strength postsupplementation with no change in 20-m wheelchair sprint performance. The supplementation protocol was effective for achieving sufficient vitamin D concentrations in elite athletes with spinal cord injury.