The mineral crucial for muscle contractions is calcium. Calcium plays a vital role in the contraction process by facilitating the interaction between muscle fibers. When muscles receive a signal from the nervous system, calcium is released from the sarcoplasmic reticulum into the muscle cells. This release enables the proteins actin and myosin to interact, resulting in muscle contraction. Additionally, calcium is important for bone health and other physiological functions, highlighting its significance in overall physical performance and health.