The effect of a short-term training period on physiological parameters and running performance: intensity...

This study compared the effect of two training strategies differing on the weekly intensity distribution on physiological parameters and running performance in moderately trained endurance athletes.

Thirty male athletes were equally divided into three groups, one following an increasing weekly aerobic intensity distribution (EXP1), one with constant weekly aerobic intensity distribution (EXP2) and a control one, following a freely chosen program (CON). Before the training intervention, athletes performed a maximal exercise treadmill test to quantify the different zones allowing training to be controlled, based on blood lactate concentration values (BLa), over a 4-week period. Changes in exercise heart rate (HR), running velocity and rate of perceived exertion at three exercise intensities corresponding to 2.5, 4 and 8 mmol·L-1 of BLa were analyzed at three testing conditions: before (pre), after two (mid) and four weeks (post).

A significant increase (P≤0.05) in running velocity at the intensity of 8 mmol·L-1 in EXP1 group was revealed at mid (5.5%) and postcondition (11.5%), while EXP2 group showed a significant decrease in exercise HR at 4 mmol·L-1 between pre- (6.7%) and post-condition (9.0%) (P≤0.05). The rest of the examined variables showed only trivial changes in both experimental groups at all testing conditions (P>0.05). In addition, no changes were observed in CON group in any of the variables tested.

These results demonstrate that depending on the training goal, different intensity variation strategies should be followed to induce the desired adaptations.