PENGARUH PEMBERIAN LATIHAN KONTRAKSI ISOMETRIK VOLUNTER DENGAN ATAU TANPA ELECTRICAL MUSCLE STIMULATION PADA KEKUATAN KONTRAKSI OTOT LENGAN BAWAH

Abstract

Background: Electrical Muscle Stimulation (EMS) is known by its function in increasing muscle strength. Forearm muscles are one of the muscles of the body and commonly used for many activities. Aim: To determine the effect of the combination exercise of EMS and voluntary isometric contraction to increase forearm muscles strength. Methods: The study was experimental research with two groups pre and post design and conducted at Physiology Laboratory Medical Faculty Diponegoro University (MFDU) on period March 2016.The subject was student of MFDU (n=12) divided into two groups, namely the combination of EMS and isometric voluntary contraction exercise group (n=6) and isometric voluntary contraction exercise group (n=6). Forearm muscle strength was measure using handgrip dynamometer at pre, and after 4 weeks exercise. The difference of forearm muscle strength between and within groups were analyze using paired t-test, unpaired t test, Mann-Whitney test, and wilcoxon test. Result: Delta of the right forearm muscles contraction in the EMS+isometric voluntary contraction exercise group is 7,8+2,33 kg, significantly higher than in isometric voluntary contraction exercise group 4,9+0,85 kg (p=0,005). Delta of the left forearm muscle contraction in the EMS+isometric voluntary contraction exercise group is 3,2+2,19 kg, also significantly higher than in isometric voluntary contraction exercise group 3,4+0,39 kg (p=0,002). Conclusion: The increased of forearm muscle contraction strength in combination exercise of EMS and voluntray isometric contraction group was significantly higher than voluntary isometric contraction exercise only. Key words: EMS, isometric contraction, contraction strength, forearm muscle, handgrip dynamometer.