The effect of acute and short term glucocorticoid administration on exercise capacity and metabolism

OBJECTIVES: Glucocorticoids (GC) are commonly used in the treatment of inflammatory conditions. Chronic GC administration has severe side effects that can decrease exercise capacity and, as a result performance. The side effects of acute (single dose) and short term (<7 days) GC administration are less severe, therefore the impact on exercise performance is unclear. Consequently, it is of interest to determine the influence of acute and short term GC administration on exercise capacity and performance and investigate the relationship with metabolism. DESIGN: Review article. METHODS: Included in the review were studies with healthy volunteers that reported exercise capacity and performance outcomes following acute and short term GC ingestion. Additionally, the relationship of exercise, GC ingestion and metabolism was investigated. RESULTS: Acute GC treatment appears to have minimal effects on exercise performance at intensities between 60 and 90% of VO2max. Short term GC treatment improved performance in the majority of studies at various exercise intensities. In general, blood glucose values increased whilst insulin and lactate values remained unchanged following GC administration. However, inconsistencies in metabolic results are present and may be due to variations in exercise protocols and the type and dosage of drug treatments. CONCLUSIONS: Acute GC administration has a minimal effect on exercise capacity and performance while short-term GC administration is likely to improve performance. Future studies should focus on the effects of GC on exercise performance and exercise metabolism during and post exercise to determine the effects on exercise capacity.