There are three main constitutional types: the ectomorph (air type), the mesomorph (fire type) and the endomorph (water type).
We are all a combination of all three, although one or more may dominate in your constitution.
How you find balance will differ depending on your constitution.
Lower impact training such as bodyweight exercises are a safer way for them to exercise. This helps them build more strength safely, which they tend to lack. Exercises of a longer duration will only deplete already low reserves. Although it will give them the high they crave, and undo the stress they tend to accumulate, it will not offer them the balance they need. Less is more for this type, which may mean doing less more often, or doing more in less time, as long as they are adequately warmed up and feeling energetic.
Fire types' ambition can be facilitated with more vigorous routines to express some of their immense drive and will power. They have moderate endurance, however, so would benefit from slowing down throughout a workout, emphasizing a longer cool down.
Giving less than 100% all the time creates more space for things to happen naturally, without injury.
Gentle encouragement is needed to keep water types moving. Once stores of energy are unblocked, they have the greatest endurance of any type. They may benefit joining groups to give them the motivation to continue with exercise, while repeating exercises keeps them moving, except when more strenuous if held for longer. This will give them the intense workout they need to stay balanced. Starting slow keeps this type going once they have tapped into their reserves.