Supervisors info:
Τερζής Γ., Καθηγητής, ΣΕΦΑΑ, ΕΚΠΑ
Μπογδάνης Γ., Καθηγητής, ΣΕΦΑΑ, ΕΚΠΑ
Πασχάλης Β., Αναπληρωτής Καθηγητής, ΣΕΦΑΑ, ΕΚΠΑ
Summary:
The aim of the study was to examine the exercise-induced muscle micro-tears following resistance exercise where each set was performed until momentary muscular failure. Eleven women (age: 23.6±3.1 years, body mass: 60.6±6.5 kg, height: 166.3±3.5 cm) without any experience in systematic resistance exercise, performed 6 sets in dumbbell elbow flexion with a load of 70% (1RM) to momentary muscular failure in each set for one upper extremity. Ten minutes later, the opposite extremity performed the same exercise with the exact same total number of repetitions, the same range of motion, the same tempo, at the same percentage of maximal strength, but having divided the number of repetitions into 10 sets, to avoid momentary muscular failure in each set. Before, 1 hour after, as well as 24, 48, 72, 96 hours after the exercise stimulus, the maximum isometric strength during elbow flexion, the subjective sensation of pain, the extension angle of the elbow joint, the thickness and the echo intensity of the elbow flexor muscles were measured for each upper extremity. Results were analyzed by two-factor repeated measures analysis of variance with a statistical significance level of p<0.05. Muscle strength decreased significantly for the exercise extremity to momentary failure and this decrease was maintained 4 days later (F= 23.759, p<0.001). In contrast, in the extremity that was trained without reaching exhaustion, strength decreased only immediately after exercise. In addition, only at the training extremity to momentary failure was an increase in muscle soreness (F= 4.616, p<0.01) and an increase in echo intensity of the brachialis anterior and biceps brachii muscle (p<0.001). In conclusion, the performance of resistance exercise to momentary muscular failure should be included into the factors of muscle micro-tears to be applied or not, according to the training goal.
Keywords:
delayed onset muscle soreness, ultrasound, maximal strength, elbow flexors
