Which of the following statements is true? select one: a. people do not need calcium throughout the entire life. b. people develop their peak bone mass during the first four decades of life. c. the skeleton no longer adds to bone density after 20 years of age. d. the bones begin to lose density after 40 years of age regardless of calcium intake.

Describe specific ways your friend can use frequency, intensity, time, and type to safely apply the overload principles to his workout schedule. provide two ways per training principle. sunday30-minute bike ride monday20 push-ups, 10 squats, and 20-minute jog tuesday30-minute bike ride wednesdayrest thursday20 push-ups, 10 squats, 25 curl-ups, and 20-minute jog friday30-minute bike ride saturdayone-hour walk