you maintain proper form and run efficiently, even through fatigue. With strong lower abs and lower-back muscles, such as the erector spinae, it's easier to stay upright. If your core is weak, you may end up shuffling, slouching and putting too much

Painful, paralysing and PB-unfriendly, cramps can strike at any time. "There's no one definitive cause," saysDr Steve Ingham, head of physiology at the English Institute of Sport (eis2win.co.uk). Research in the Muscle & Nerve Journal shows

UAN: Article type:++needs pics++-->These stretch more than one muscle group at once – including your upper body, an often-neglected area in runners. 1. Downward-facing dogKeep your feet hip-width apart and your hands shoulder-width apart. Keep

-rate variability," says Dr Tim Church, coauthor of exercise guide Move Yourself. Think of it as having only two gears to tackle the Alpe d'Huez when you need 20. Low heart-rate variability leaves you at a higher risk for a fatal heart attack.Muscles:When you

Ouch Your muscles burn – and basically everything's on fire. Science Many call this "going anaerobic," but there's little evidence that the pain arises from too little oxygen (or too much lactic acid). Rather, your brain recognises that you're too

© Getty ImagesPut simply, good core stability is one of the most effective ways to prevent injuries and improve running efficiency. The groups of muscles that make up your core section provide essential support so strengthening your core should form

, but also by boosting the immune system. And by learning how to reduce muscle tension caused by intense activity, recovery is accelerated and muscle soreness reduced, which in turn improves flexibility and can allow you to continue training hard. Making

you stay healthy. A poor recovery strategy can lead to fatigue, chronic tiredness, muscle soreness, poor sleep and increased susceptibility to infections and injury.   Recovery in the body involves a complex process of adaptation to the physical stress

more severe are ‘bad breathing’ (for instance a rapid, shallow breathing pattern) and weakness or fatigue of your breathing muscles. Advancing age is strongly linked to breathing muscle weakness, as is the amount of hard breathing work that you do (I

more quickly and shallow.What's the cure? As with any cramp, the best treatment is to stretch the muscle. To do this, try altering your breathing pattern. Take a deep breath in from your belly (not your chest) as quickly as you can, to force