Strength training - Swimming

Push-up Balance on your toes and hands: hands just wider than shoulder-width apart. Straighten back and legs. Breathe in, lower your torso to the floor by bending your elbows to 90 degrees. Engage (tense) your abdominal muscles to help to keep legs straight. Breathe out and push back up to the starting position. Routine: Perform 3 x 5 push-ups with 45 seconds rest between sets. Gradually build up until you can manage 3 x 15 Photograph: John Watson/John Watson

Squats Stand with feet almost shoulder-width apart, neck relaxed. Contract your abdominal muscles and breathe in. Release your knees until they are over your toes and your thighs are parallel with the ground. Keep your heels on the ground and the weight over the back of the foot. Keep your back straight and hold your arms out. Breathe out and press through the heels to return to the start position. Routine: Perform 2 x 15 squats with 45 seconds rest between sets Photograph: John Watson/John Watson

Abdominal crunches Lie on your back, knees bent, feet flat on the floor, hands by your ears. Curl your shoulders forwards, keeping your lower back on the floor. Tense the abs, breathing out as you lift and in as you lower. Keep a space the size of a tennis ball under your chin, so your head stays in line with your spine. Each rep should take about four to five seconds. Routine: Perform 2 x 20 reps with 30 seconds rest. Gradually build up to 4 x 25 Photograph: John Watson/John Watson

The plank From lying face down, push yourself up on to your elbows and feet. Keep a straight line through the head and hips, without raising your bottom too high. You should feel no tension in your back - if you do, lift your hips a little. If this is too difficult, perform the hold from the knees, again, maintaining a straight line, with no tension in the lower back. Routine: Hold for 45 seconds to one minute. Gradually build up the time Photograph: John Watson/John Watson

Swiss ball hamstring curl Lie on a mat and press your heels into the middle of the Swiss ball. Extend your legs and put your feet together, pointing your toes. Keep your shoulders on the floor, arms by your sides (palms down) and lift your hips off the ground, breathing out. Pull the ball towards your bottom until your feet are flat on its surface. Inhale and push the ball back to the start position. Routine: Perform 2 x 10 reps with 30 seconds rest Photograph: John Watson/John Watson