Walking versus running
Health: Pavement pounding helps to improve bone density and so helps prevent osteoporosis; overdo it, though, and you risk stress fractures in your bones.
Walking is far less risky in terms of injury but with less risk comes a smaller pay-out in terms of health benefits: your cardiovascular system and your muscles are worked harder when you run.
Score: Running: 2 Walking: 1
Calorie burn: Running pips walking at the post by as much as 250* more calories every 30 minutes. (Figure based on a 4mph walk and a running pace of 7mph.)
Score: Running: 1 Walking: 0
Enjoyment: Running may give you a natural 'high' through the production of feel-good hormones, but walking offers some unique pleasures; walkers can talk, laugh and even get from a to b without the need for a shower once they've arrived.
Score: Running: 1 Walking: 1
Overall winner: Running
Cycling versus swimming
Health: Both are low-impact exercises – water supports you while swimming; and during a bike ride your weight is taken by the seat and handlebars – which is good news for your joints. Weight-bearing exercises are best for preventing osteoporosis, however, so bad news for your bones.
Where you cycle plays a large part in how healthy it is for you too: if you cycle in busy traffic you're putting both your lungs and heart at risk, according to research undertaken by the British Heart Foundation. They found that study participants suffered from blood vessel damage up to six hours after exposure to high pollution levels while cycling.
You won't be exposed to air-borne pollutants while swimming, although you are more likely to encounter non-life-threatening nasties such as veruccas and athlete's foot, not to mention the occasional plaster.
Score: Cycling: 1 Swimming: 2
Calorie burn: Neither swimming nor cycling will burn many calories unless you do it at speed, getting out of breath in the process. If, for example, your cycling style is more Mary Poppins (slow and steady at 5mph) than Lance Armstrong (feet spinning the pedals at 13mph), you'll burn nearly 200* fewer calories for every 30 minutes you ride.
Water-lovers have it just as tough: cruising through the water like a swan will burn about 100 fewer calories than vigorous swimming per 30 minutes. Added to that, research published in the International Journal of Sport Nutrition and Exercise Metabolism found that swimming in cool water increases appetite making you more likely to pig-out after your pool session.
Score: Cycling: 1 Swimming: 0
Enjoyment: Unlike cycling where the scenery changes as you move, swimming in a pool can make you feel a bit like a bored goldfish. Cycling also allows for companionship; attempting a conversation while swimming is likely to result in a swallowing of words, not to mention a large mouthful of water. That said, being immersed in water is incredibly calming, so if you're stressed and need time alone it could be the perfect remedy.
Score: Cycling: 1 Swimming: 1
Overall winner: it's a draw!
Tennis versus squash
Health: The fast pace of squash boosts heart rate and stamina. Tennis is also great for your ticker and staying power, but how much you get out of it depends on how hard you push yourself.
You can choose to play a leisurely 'friendly' game of tennis or go all-out on a fierce competition; with squash, you and the ball will be energetically bouncing off four walls whatever kind of game you play.
Squash also requires faster response times and so keeps you sharp, but it does put you at more risk of injury from a ball, not to mention your joints. Both will enhance your spatial awareness and coordination.
Score: Tennis: 1 Squash: 1
Calorie burn: Squash burns approximately 70 calories* more for every 30 minutes you play. The equivalent of one slice of bread. Whichever way you cut it, whether you choose to hit a squash or tennis ball is unlikely to make a huge difference to your waistline.
Score: Tennis: 0 Squash: 1
Enjoyment: Tennis is nearly five times as popular as squash, with approximately five million people serving in courts around the UK. Finding a squash partner you hit it off with, therefore, might prove more difficult.
Score: Tennis: 1 Squash: 0
Overall winner: It's a draw!
Snowboarding versus skiing
Health: Despite reaching speeds of up to 20-25mph while skiing or boarding, the average snowsports enthusiast doesn't give his or her heart much of a workout during a session on the slopes.
If you do find yourself gasping for breath – a good indicator that you've worked your heart – it's more likely to be caused by the breathtaking scenery than physical exertion.
Both skiing and boarding will improve your balance and coordination, however, and give your lower body muscles an excellent workout. Skiing achieves pole position, however, because it also works your arms and shoulders.
Score: Skiing: 2 Snowboarding: 1
Calorie burn: If weight loss is your goal, you can take your pick of snowboarding or downhill skiing as they burn approximately the same number of calories, approximately 280 during a 30-minute session.
Score: Skiing: 1 Snowboarding: 1
Enjoyment: Getting close to nature makes us feel better – it's called the 'biophilia effect' and while skiing or boarding you're likely to enjoy some of the world's most spectacular mountain scenery.
Score: Skiing: 1 Snowboarding: 1
Overall winner: skiing
*All figures based on a 70kg person (10 stone 10lb), 30 minutes' activity.
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