FUNCTIONAL EVALUATION SECTION   

Medicina dello Sport 1999 December;52(4):235-41

Copyright © 1999 EDIZIONI MINERVA MEDICA

language: English

Hormone levels following leg press exercise at an individual physical working capacity in male students

Jurimae T., Jurimae J., Leppik A.

Institute of Sport Pedagogy, University of Tartu, Tartu (Estonia)

The aim of the ­present ­study was to inves­ti­gate the use­ful­ness of max­i­mal dura­tion leg ­press exer­cise at an indi­vid­u­al phys­i­cal work­ing capac­ity (PWC) lev­el dur­ing ­sport prac­tice or rec­re­a­tion­al pur­pos­es in ­male phys­i­cal edu­ca­tion stu­dents (n=18). Firstly, indi­vid­u­al PWC was meas­ured ­using a ­cycle ergom­e­ter ­test. Three pro­gres­sive work­loads (150, 200 and 250 W) for a peri­od of ­four min­utes ­were ­used. Individual PWC was cal­cu­lat­ed by extrap­o­la­tion at the lev­el of pre­dict­ed ­HRmax (205 - 1/2 age). Secondly, an indi­vid­u­al PWC of two-­legged leg ­press exer­cise was deter­mined sim­i­lar­ly to the ­cycle ergom­e­ter ­test. The ­loads ­were 30, 45 and 60% of indi­vid­u­al 1 rep­e­ti­tion max­i­mum for a peri­od of 4 min­utes and sub­jects per­formed 15 rep­e­ti­tions per min­ute. After 3 ­days of ­rest, leg ­press exer­cise for max­i­mal dura­tion was per­formed at an indi­vid­u­al PWC (15 rep­e­ti­tions per min­ute). Venous ­blood sam­ples ­were ­obtained 3 min­utes ­before and imme­di­ate­ly ­after the ­test. Testosterone, cor­ti­sol (C), sex-hor­mone-bind­ing-glob­u­line, glu­cose (GL) and lac­tate (LA) con­cen­tra­tions ­were meas­ured. Significant cor­re­la­tion ­between PWC val­ues of ­both ­tests was ­found (r=0.70). Mean leg ­press exer­cise dura­tion and HR ­were 450.2±99.1 sec and 137.4±14.2 ­beats·min-1, respec­tive­ly. Only LA (­from 1.92±0.91 to 7.62±2.83 ­mmol·l-1) and C (­from 388.83±138.12 to 470.72±155.06 ­nmol·l-1) con­cen­tra­tions in ­blood ­were sig­nif­i­cant­ly ­increased, and the con­cen­tra­tion of GL ­decreased (­from 5.25±0.80 to 4.54±0.84 ­mmol·l-1). In sum­mary, the rel­a­tive­ly ­short leg ­press exer­cise at an indi­vid­u­al PWC lev­el ­only mod­er­ate­ly influ­enced the ­blood ana­bol­ic/cat­a­bol­ic ­ratio. However, the addi­tion of HR meas­ure and the use of cal­cu­lat­ed PWC in leg ­press exer­cise dur­ing ­sport prac­tice or rec­re­a­tion­al pur­pos­es ­needs ­more inves­ti­ga­tions ­before any con­clu­sions can be ­drawn.