Effects of load and training modes on physiological and metabolic responses in resistance exercise

The aim of the study was to examine the effects of three different loads (LOAD) in combination with four different exercise modes (MODE) on physiological responses during and after one fatiguing bout of bench press exercise. Ten resistance-trained healthy male subjects performed bench press exercise each at 55% (LOW), 70% (MID) and 85% (HIGH) of 1 repetition maximum (1RM) for as many repetitions as possible and in four training modes: 4-1-4-1 (4-s concentric, 1-s isometric, 4-s eccentric and 1-s isometric successive actions), 2-1-2-1, 1-1-1-1 and MAX (maximum velocity concentric). Oxygen uptake was measured during exercise and for 30-min post-exercise. Maximum blood lactate concentration (blood LA(max)) and heart rate (HRmax) were also determined. Number of repetitions (REPS) and exercise time (EXTIME) were recorded and accumulated lifted mass (MASS), defined by REPS x lifted mass, was calculated. LOAD had a significant effect on REPS (LOW > MID > HIGH, p < 0.01). A significant increase of REPS was obtained exercising at a faster MODE except from 1-1-1-1 to MAX (p < 0.01). EXTIME significantly decreased with increasing LOAD (LOW > MID > HIGH, p < 0.01 for all) and faster MODE (4-1-4-1, 2-1-2-1, 1-1-1-1 > MAX; p > 0.01). MASS decreased significantly with increasing LOAD (p < 0.01) but increased with a faster MODE (p < 0.05) with the exception of 1-1-1-1 to MAX. MODE had a significant effect on (4-1-4-1 > MAX; p < 0.05). LOAD had a significant effect on consumed O-2 during exercise (LOW > MID and HIGH; p > 0.01) and on blood LA(max) (LOW and MID > HIGH; p < 0.01). The data indicate that physiological responses on different resistance exercises depend on both the load and the velocity mode.