As important as it is to train hard in the pool, swimmers need to complement those workouts with strength and conditioning or, as many others call it, dryland training. The purpose of dryland training is to stretch and strengthen the muscles used in swimming because it's just simply not possible to be in a pool at all times. These are some great CoachUp certified exercises that will help you work on your core, arms, and legs all without a pool!
To begin, lie flat on your back. Place your hands at your side, or under your butt for extra help, and lift your legs about two inches from the ground. Keep your legs straight and toes pointed and then quickly flutter your legs about two inches up and down without touching the ground. This exercise will not only work your lower abs and legs but will also simulate the kick needed for freestyle and backstroke.
Whenever you push off the wall after a flip-turn, you're essentially doing a squat. You can augment your training by doing squat repetitions outside the pool to build up the muscle strength that will give you real acceleration coming off the wall. If you’d like to add extra resistance, do weighted squats using a barbell or a dumbbell. By getting accustomed to squatting with extra weight on your body, pushing off the wall will feel easier, especially during the last lap of an extremely demanding race.