Metabolic responses to interval training programs of high and low power output

The metabolic responses of 30 college-aged males were compared following high power (30-sec runs with 19 repetitions-Group HP) and low power (120-sec runs with 7 repetitions-Group LP) interval training programs (8-wk, 3 days/wk). Measurements included: maximal aerobic power (Vo2max, open circuit spirometry); maximal lactacid capacity (net-LAmax, blood LA accumulation following exhaustive exercise); net energy production (net Vo2 and netLA) following a 2-min run that was exhaustive before but not following training; and maximal muscular power (stair-climbing procedure). The results indicated: 1) significant but equal increases in Vo2 max in both groups; 2) no change in either group in netLAmax; 3) net Vo2 during the 2-min run was unchanged, however, netLA was significantly greater in Group LP; 4) no changes in either group in muscular power. It was concluded that low power and high power output interval training programs elicit similar changes in maximal aerobic and anaerobic metabolism, and that the physiological and or biochemical changes responsible for lowered lactic acid production during heavy, but submaximal exercise following training are produced to a greater extent by the low power program.