Six male long-distance runners participated in this study to evaluate the responses to exercise at 90% and 100% vV02max. Subjects participated in five maximal exercise tests: one incremental, three tests at 90% vV02max, and one test at 100% vV02max. The results of this study demonstrate that V02max can be elicited in a constant-velocity test at 90% vV02max.

Acute effects of repeated sprinting upon serum creatine kinase (CK), lactic dehydrogenase (LDH), and isozymal activities were studied in five collegiate runners (R_s) and six non-runners (NR_s ). After an intermittent running treadmill test, blood sampling showed three-fold mean increases in CK with no change in LDH in both groups; group differences were insignificant (p>.05). Results suggest (1) intense anaerobic exercise produces moderate enzyme elevations; (2) relatively equivalent exercise intensities are critical to enzyme responses in exercising individuals of varying fitness levels; and (3) exercise-induced enzyme release may be consequential to muscle cell membrane permeability changes from decreased intracellular high-energy phosphates.

The purpose of this study was to examine the effects of different surfaces on lower limb motion and encountered pressures at two locations on the plantar surface of the right foot. Nine females performed five trials for each of four surface conditions. The results provided no evidence for surface-related changes in experienced foot contact pressures. Both asphalt and grass surfaces resulted in the shortest relative time of forefoot immobility. No surface related differences were found for the range of pronation.