Glucocorticoids improve high-intensity exercise performance in humans

TY - JOUR

T1 - Glucocorticoids improve high-intensity exercise performance in humans

AU - Casuso, Rafael A

AU - Melskens, Lars

AU - Bruhn, Thomas

AU - Secher, Niels H.

AU - Nordsborg, Nikolai Baastrup

N1 - CURIS 2014 NEXS 035

PY - 2014/2

Y1 - 2014/2

N2 - Purpose: It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise. Methods: Using a double-blinded placebo controlled randomized crossover design, subjects ingested either 2 × 2 mg of DEX or placebo for five consecutive days. Muscle function was investigated using one-legged kicking exercise and whole body performance was evaluated using a 20-m shuttle run and a 30-m sprint test. Results: One-legged dynamic knee-extensor exercise time to exhaustion was 29 ± 35 % (mean ± SD) longer (P < 0.05) in DEX compared to Placebo. Likewise, total running distance in the shuttle run test was 19 ± 23 % longer (P < 0.05), whereas 30-m sprint performance was unaltered. During the initial 75 s of dynamic leg extensions, peak force and rate of force development determined from an electrically evoked twitch declined in a similar way in DEX and placebo. Similarly, the EMG root mean square was similar with DEX and placebo treatment. Conclusion: Short-term dexamethasone administration increases high-intensity one-legged kicking time to exhaustion and 20-m shuttle run performance, although sprint ability and the initial loss of muscular force generating capacity are similar after DEX and placebo.

AB - Purpose: It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise. Methods: Using a double-blinded placebo controlled randomized crossover design, subjects ingested either 2 × 2 mg of DEX or placebo for five consecutive days. Muscle function was investigated using one-legged kicking exercise and whole body performance was evaluated using a 20-m shuttle run and a 30-m sprint test. Results: One-legged dynamic knee-extensor exercise time to exhaustion was 29 ± 35 % (mean ± SD) longer (P < 0.05) in DEX compared to Placebo. Likewise, total running distance in the shuttle run test was 19 ± 23 % longer (P < 0.05), whereas 30-m sprint performance was unaltered. During the initial 75 s of dynamic leg extensions, peak force and rate of force development determined from an electrically evoked twitch declined in a similar way in DEX and placebo. Similarly, the EMG root mean square was similar with DEX and placebo treatment. Conclusion: Short-term dexamethasone administration increases high-intensity one-legged kicking time to exhaustion and 20-m shuttle run performance, although sprint ability and the initial loss of muscular force generating capacity are similar after DEX and placebo.

U2 - 10.1007/s00421-013-2784-7

DO - 10.1007/s00421-013-2784-7

M3 - Journal article

C2 - 24327175

SN - 8750-7587

VL - 114

SP - 419

EP - 424

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

IS - 2

ER -