It's frustrating after working hard getting yourself into good shape when you get a cold or a niggling injury, which lays you low for a week or two.

With the shorter days and cooler weather, it's also a time of year when your exercise regimen becomes more stop-start. Added to illness and injury, that's enough of an excuse for many of us to stop exercising.

When you're feeling sluggish and daunted by the mountain to climb to regain your fitness, it's easy to think “what's the point?” But it's vital to take the long-term view; any setback is a pain, but a break can have a restorative effect. Getting in shape is not about what happens over a week or two, but what happens over several weeks and even several months.

All is not lost

You'd have to be out of action for two months to be back to square one. Missing a week's training through illness costs you only 2 to 5 per cent of your fitness. It is barely noticeable and could actually prove to be a much-needed rest. If you have to put your feet up for a month, you would still lose only 15 to 20 per cent of your fitness, which could be rapidly regained.

It's only after eight weeks that your fitness drops off a cliff and it's a long slog back to your peak. Even then, it's not so much that you've lost fitness as that you simply feel unfit because you have not generated the blood flow and physical highs of exercise. But these figures apply only to those who have been working out continuously for a year. If you keep starting and stopping, your fitness will erode much more quickly.

Don't overdo it at first When you eventually resume your routine, moderate your approach. You will be hit for six physically and mentally if you try to plunge back in after more than a week off. Reduce the intensity of your workout by 10 to 15 per cent and work your way back gradually. This is particularly important if you've been had a cold or flu because your heart is at greater risk if you try to push yourself while recovering.

Rethink your routine

You might not be able to do your usual workout, but that doesn't mean that you're helpless. Do something else, or adapt your routine. If you have a cold, you can't go for a run to get your heart and lungs working, but there's no reason why you shouldn't focus on your midriff with sit-ups and lower back work. And you can still work your legs if you are suffering from a broken wrist or arm, so it's perfectly fine to go for a run as long as you don't create another strain elsewhere.

Just stretch

Even if you feel incapacitated, you can usually still do some stretching. It may seem as though doing just a little isn't worthwhile, but injuries heal more quickly if other parts of your body are being put through their paces. Immunity is increased through regular activity.

For more on Matt, visit www.mattroberts.co.uk

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