Which of the following statements is not true?
a. muscle growth is typically completed by about age 30.
b. after age 30, there is typically a 10% loss of muscular strength until about 60, usually in the back and leg muscles
c. regular exercise has little impact on maintaining peak performance after age 30.
d. after age 60, there is a significant loss of lean muscle mass and flexibility

The correct answer is option c. "Regular exercise has little impact on maintaining peak performance after age 30".

Explanation:

It is false to affirm that regular exercise has little impact on maintaining peak performance after age 30. Actually it has been reported that regular exercise helps to maintain peak performance for almost the whole life. Performance declines is accelerated beyond the age of 70, but regular exercise helps to prevent the degree of decline even at this age.