Effects Of Different Modalities On The Muscular Function Between Repeated Bouts Of Exercise

Abstract

PURPOSE To investigated which modality would be the best way to improve the recovery of muscle function between two different sets of repeated bouts of eccentric exercise. METHODS: Thirty-six non-weight-trained subjects (age: 21.23 ± 1.68 yrs, Ht: 163.56 ±6.67 cm, Wt: 54.63 ± 6.84 kg) participated in this study. All subjects performed the first set of 30 eccentric actions (ECC1) with non-dominal elbow flexor using a dumbbell that was set at 80% of the pre-ECC1 maximal voluntary isometric contraction (MVC) force. Subjects were then randomly placed into cryotherapy (CRYO; n = 12), electrical therapy (ELEC; n = 12) or control (CON; n = 12) groups. Immediately after ECC1, the CRYO and ELEC groups received cold and transcutaneous electrical nerve stimulation (TENS) treatments, respectively, for an hour. All subjects repeated the same bout of 30 eccentric exercise (ECC2) after treatments. The MVC was assessed before, immediately after both ECC1 and ECC2, and 2, 4, 7, and 10 days (D2, D4, D7, D10) after ECC1 for all groups. Serum creatine kinase isoform (CK-MM) was analyzed before, and at D2, D4, D7, and D1 0 for all groups. RESULTS There was a significant further decrease (P < 0.05) in MVC immediately after treatment when compared to the pre-test for the ELEC, but not for CRYO and CON. The MVC for ELEC was significantly lower than CRYO (P < 0.05) on day D4, D7 and D10. The MVC of ELEC was also significantly lower than CON (P < 0.05) on D7 and D10. There was a significant increase in CK-MM on D4 and D7 (P < 0.05) when compared to the pre-test for the ELEC, increased CK-MM on D4 (P < 0.05) for CON, but no significant difference among days for CRYO. The CK-MM for ELEC was significantly greater than CRYO and CON on D2, D4, D7 and D10 (P < 0.05). However, there were no significant differences between CRYO and CON on any day. CONCLUSIONS The recovery outcomes showed cryotherapy is the most beneficial for muscle damage management between repeated sets, and lower frequency electrical therapy is the least usefal for muscular function recovery.