Temperature Changes in Human Skeletal Muscle during Single Leg Dynamic Knee Extension Exercise

Abstract

The beneficial cardiovascular adaptations associated with endurance exercise are widely acknowledged, but the exact mechanisms mediating such adaptations are not well understood. Research has indicated that acute sustained postexercise vasodilation is induced by histamine receptor activation, and recent studies suggest that increased intramuscular histamine is responsible for this response. Currently, the specific exercise related factor or factors that trigger histamine release is unknown. Increased skeletal muscle temperature has been hypothesized as the key exercise condition that mediates histamine release; the current study is the first phase of an investigation that will ultimately address this hypothesis. This study examined the skeletal muscle temperature changes that occur during 60 minutes of single leg dynamic knee extension exercise at 60% of maximal work rate. The equilibration temperature specific to this exercise model was 39.15 ± 0.69 °C. The knowledge developed in this study will enable future studies to investigate the relationship between increased skeletal muscle temperature and histamine release.