Additional Effects of Taurine on the Bene fi ts of BCAA Intake for the Delayed-Onset Muscle Soreness and Muscle Damage Induced by High-Intensity Eccentric Exercise - Advances in Experimental Medicine and Biology - page 168

Fig. 18.1 Schematic showing of the protocol of the present study. Subjects were supplemented
(BCAA or/and taurine) for 14 days before the exercise experiment, exercise on day, and following
4 days. Abbreviations : Pre suppl . pre-supplementation, Before before the exercises, After immedi-
ately after the exercise, 1 ~ 4 following 4 days, ECC eccentric exercise, Soreness muscle soreness
evaluated by VAS, Blood blood sampling, Supplement supplements were amino acid consumptions
three times per day for 18 days by each condition

The present study was carried out in accordance with the Declaration of Helsinki
and was approved by the Human Subjects Committee of the University of Tsukuba.
All subjects provided informed written consent.

18.2.2 Exercise Protocol

On the exercise day, the subjects assembled to laboratory at 7 a.m. after an overnight
fasting, and ingested the amino acid supplement before 15 min of the ECC. In the pres-
ent study, the exercise protocol to induce the DOMS and muscle damages in the biceps
brachii muscle was modified from the method of ECC reported by Lavender et al.
(Lavender and Nosaka 2008 ). Before at least a week of the supplementations, maximal
voluntary strength of isometric contraction (MVC) in the nondominant arm was mea-
sured at 1.57 rad (90°) elbow flexion in each subject. In the exercise day, subjects were
loaded to repetitive dumbbell lowering by 90% MVC of individuals (11.7 ± 0.4 kg) as
voluntary eccentric muscle contraction (Fig. 18.2 ). Subjects were seated on a bench
with the arm positioned in front of the body resting on a padded support so that the
shoulder was secured at an angle of 0.79 rad (45°) flexion, and the forearm was kept
supinated throughout exercise. ECC protocol consisted of six sets of five actions from
an elbow flexed at 90° to an extended position in 5 s keeping the velocity as constant as
possible by following the investigator's counting. After each muscle action, the inves-
tigator returned the dumbbell to the starting position to prevent any muscle actions by
the weight. Rests were taken 3 s and 2 min between muscle actions and sets, respec-
tively. This protocol using 90% MVC induced natural muscle damage by eccentric