Vitamin D Supplementation Improves Aerobic and Resistive Exercise in Men
Med Sci Sports Exerc May 2014 - Volume 46 - Supplement 1 5S p 474
Rachel L. Darr
Chronic exercise benefits heart rate (HR) and perceived exertion (RPE) in humans. Improved lifestyle via diet, leads to healthier physiological outcomes and greater performance during activity. Specifically, sufficient serum levels of Vitamin D are linked with muscular maintenance and the further ability to perform adequate exercise.
PURPOSE: To determine if Vitamin D supplementation alone, can improve outcome measures in acute bouts of Aerobic (AB) and Resistive (RT) exercise in healthy middle aged men.
METHODS: 13 Vitamin D insufficient and deficient (20.0±7.7ng/mL) men (39.0±8.6yo) were screened and enrolled via a Physical Activity Readiness Questionnaire. A Submaximal VO 2 and One-Repetition Maximums (1-RM) were completed. Every subject underwent 3 types of acute exercises for one hour on different days (randomizing the order of; stretching (ST), AB, and RT). Each exercise hour was separated by at least 2 days. ST, as an attention/time control visit, altered passive stretch and relax movements every 10 seconds. AB exercise
involved moderate intensity treadmill walking. RT rotated moderate intensity 50% 1-RM; 15 and 10 repetitions of squat and bench press (5 sets), followed by leg press and lat pull down rotations (5 sets), and finished with squats and bench. The 3 visits were repeated after a month of daily supplementation of Placebo (7 subjects) or 4000IU Vitamin D3 (6 subjects). HR and RPE were collected every 5 minutes of exercise.
RESULTS: No differences were noted with Maximum HR(MaxHR) and Time to Maximum HR(TMaxHR) between AB(128bpm,49min) and RT(132bpm,41min) but both were lower for ST(88bpm, 28min) vs. AB(p<0.0001, p<0.002) and RT(p<0.0001, p<0.03). Vitamin D intake reduced MaxHR only during RT (141 to 123bpm, p<0.05). Maximum RPE(MaxRPE) and Time to MaxRPE(TMaxRPE) were lower in ST(8, 18min) than both AB(15, 44min, p<0.001) and RT(16, 50min, p<0.0001). Vitamin D intake reduced TMaxRPE only during AB (52 to 36min, p<0.05).
CONCLUSION: Aerobic and anaerobic workloads were well matched with no differences in HR and RPE. Vitamin D supplementation may permit an individual to increase their aerobic workout time, owed to a longer time to reach MaxRPE, and increase their anaerobic production, due to a lower MaxHR.