The chin - up is one exercise that can be used to strengthen the biceps muscle. This muscle can exert a force of approximately 8.00 x 102 N as it contracts a distance of 7.5 cm in a 75 - kg male.3 (a) How much work can the biceps muscles (one in each arm) perform in a single contraction? (b) Compare this amount of work with the energy required to lift a 75 - kg person 40. cm in performing a chin - up. (c) Do you think the biceps muscle is the only muscle involved in performing a chin - up?