Which principle of exercise is concerned with maintaining a challenging workout?
a. balance
b. regularity
progression
d. overload
oo oo
select the best answer from the choices provided.

D. overload

Explanation:

The overload principle is concept used in sport fitness. The principle states that athletes must continually work harder and the exercises and trainings must become more challenging in order to improve, because their bodies adjust to existing workouts.

hope it helps:)

teens need 8-10 hours of sleep. it kind of depends on what time you get up. but prob around 10 or 11 p.m. or 11 or 11: 30 p.m.

the answer is c, the development of reading and writing in young children