Siege

If you need these activities to pass a test, then just focus on the activities. within 5 weeks your muscles will easily become accustomed to these exercises.

If you want to get into better shape overall, then do extra exercises (but not just NOW, do it throughout your life!)

The number of times you do it is not the entire equation. If you do 20 push ups, 25 situps and 600 step ups once, depending on your fitness level/recovery rate you could do it more than twice. What i'm trying to get at is number of sets per exercise session is something you need to keep in mind, not just the number of sessions.

Adding a 25lb pack to your step ups may not be that helpful immediately if you cannot do the exercise yet. Make sure you can do it without a hindrance first.

My best advice, as someone who specializes in "holy-shit-i-have-a-tournament-next-week-and-i-need-to-get-into-shape" fitness is to start somewhere comfortable yet challenging, make sure you get plenty of rest, and try your best to do your exercises at least 3 times a week while ramping up your exercises slowly. since you have 5 weeks, you can increase the amount you do per week. ie: if you could only do 15 pushups, aim for 17 in week 2, 20 in week 3 etc.

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