Question

What training principle states that you must continue to exercise to maintain fitness?

Answer 1

that or diet

Answer 2

oh misread the question, and it all just depends on what you do like doing the littlest thing with heavy weight could make a difference but i dont know the principles so yeah another way of explaining it i guess. its mostly common sense though because if you want to get better at something you must practice it on a daily basis but for workout you need to do it only 2-3 days a week well if you use weights or something that includes strength well idk if jogging would count as a workout really but sprinting you could do like 30 mins. a day because it builds muscle. and when you stop exercising your body weakens and your muscles increase to where they become weaker