Whether it's the lido or the sea, swimming is an incredible all-over body toner - a speedy crawl will burn about 100 calories every 10 minutes, and breaststroke about 60.
Improving core stability enables you to be more streamlined and efficient in the water. Try this Pilates exercise before you take a dip - it's perfect for strengthening your back, hamstrings and buttocks. Lay on your front, forehead on the floor, arms stretched above your head. Engage your core-stability muscles and slowly lift your head, chest and arms, looking at the floor and keeping the neck long. Then lift the legs with toes pointed. Now, at a fairly fast rhythm, start pulsing the opposite leg and arm up and down (so right arm and left leg go up at same time, followed by left arm and right leg). Keep your core still and engaged throughout, and don't let your hips rock. Keep breathing. Aim for 30 seconds, relax and repeat.
Now you're ready to swim.
If you want to look good in your bikini/swimming shorts this summer, tennis is ideal. It burns a whopping 500 calories per hour, does wonders for your cardio fitness and no part of your body will remain untoned.
To boost the explosive muscle power needed for changing direction in tennis, try this. Lay down string/ribbon/a scarf to jump over. Stand to the side of it, bend your knees and jump sideways over the string, landing lightly with both feet. Use your arms to aid you by swinging them up as you jump and back as you land. As soon as your feet hit the ground, spring back up and over to the other side without pausing. Jump back and forth in a rhythm for as long as you can with good form.
It's the simplest way to get fit - the only piece of kit you need when you walk is a supportive but lightweight pair of shoes (we like Merrell's Capra; merrell.co.uk). Just 20 minutes of vigorous walking a day can reduce the risk of heart attacks, strokes and some cancers by up to 30%, compared with being sedentary, according a 2015 study. Vigorous is the key though - aim for 124-155 steps per minute (the average person takes about 94-105).
Improving body alignment and walking posture by working on core stability helps reduce the risk of developing aches and pains on long walks.
Sit on a Swiss ball (large, inflatable exercise ball), with knees bent, feet together, back straight. In a slow, controlled movement, lift one foot off the floor and hold for 10 seconds. If you wobble, put the foot down and try again. Repeat 10-12 times on each foot, rest and repeat.
Both sports will do wonders for cardio fitness, muscle tone and core stability. Sailing will burn about 400 calories per hour, especially if it's windy, and rowing can use up an impressive 670. To find a course or club near you, visit rya.org.uk or britishrowing.org.
A strong core means you can hold a better posture throughout the stroke in rowing, and maintain good positioning and balance when hiking out over the side of the boat in sailing. Try this v-sit, an intense workout for core-stability muscles. Sit with your legs out straight and raise your arms out in front of you. Slowly lean back and raise your legs, toes pointed, to 45 degrees to form a V shape with your trunk. Hold your arms alongside your knees. Ensure that your hips and core stay engaged, and balance on your sit bones (the bones in your bottom). Hold for as long as you can with good form - ideally, 30 seconds or more.
Both require speed, power and agility, offering you fantastic fitness benefits - they will make both upper and lower body strong and sleek, as well as boost cardio fitness. You'd be burning off about 450 calories per 60-minute game of netball, and playing basketball for 40 minutes would burn about 360.
To boost your ability to jump quickly after landing, try jumping squats. Stand with feet hip-width apart, hands on hips. Bend into a quarter-squat (not a full one), then jump into the air, keeping your hands on your hips. As you land, go straight back into the squat and jump again without pausing. It should be a continuous movement. Ensure your knees don't go out beyond your toes - the squat is achieved by sticking your bottom out. Start with two sets of eight with a rest in between, and build up.
If you have any health conditions or injuries, consult your doctor before doing these exercises.