What happens when I run?

How do running and walking differ?
‘It’s all about speed and pressure,’ says chartered physiotherapist Sammy Margo. ‘When you walk, you load your joints with three to four times your body weight. When you run, you’re loading them with six to eight times your body weight.’ With walking, you always have a foot on the ground; when you run, there are moments when both feet are off the ground.

What’s going on inside your body?
‘When you run, your brain sends a signal to the muscles in your legs to start contracting or lengthening, depending on which muscles they are,’ says Margo. ‘Your heartbeat and breathing rates increase, and you start taking deeper breaths.’ That’s because your muscles are working harder, and so need more oxygen to function, and to remove the waste product, carbon dioxide.

Why is running good for you?
It’s a very cheap option. ‘All you need is a decent pair of running shoes,’ says Margo. ‘Visit a reputable sports shop, where they can analyse your running gait.’ Apart from improving your fitness, running also gets you outside in the fresh air. You can even make it part of your journey to work.

What else do you need to know?
Start slowly. ‘Too fast and you risk pain, injury, disillusionment and giving up,’ says Sam Murphy, co-author of Running Well (Kyle Cathie, £14.99). ‘Progress from walking to mixing bouts of walking and running and then to running only.’ And it’s important to be consistent. ‘Your body doesn’t like sporadic training, because it doesn’t know whether it needs to adapt to a new level of challenge,’ says Murphy. Knee pain is common for runners. ‘This can be caused by tight or weak muscles, your footwear, and the frequency, duration and intensity of your running,’ says Margo. If you run on roads and pavements, take note. ‘Beware of running on the edge of a steeply cambered road, as the tilted surface can contribute to injury,’ says Murphy.

What kind of diet can help me run?
Eating low glycaemic index (GI) carbohydrates can help, as they are the best source of energy. ‘Types of carbohydrates that release their energy slowly, such as brown rice, lentils and porridge oats, have a low GI,’ says Murphy. Lean protein – such as chicken or tofu – helps to build and repair body cells. And staying hydrated is a must. Murphy recommends isotonic sports drinks to replenish salts lost through sweating, as well as the supplement creatine, to help post-run recovery by reducing cell damage and inflammation. Take glucosamine and chondroitin to prevent joint pain. ‘The combination of these two compounds seems to improve mobility and reduce pain in the knees and hips,’ says Murphy.

Words: Hannah Fox