Just as many dieters veer from celery one week to chocolate the next, so many exercisers swing wildly from couch potato to gym fanatic and back again all too frequently.

It's well-known that this see-sawing between extremes usually leaves those trying to lose weight heavier than when they started. But there's another price to be paid by yo-yo exercisers. All these bursts of intense exertion followed by weeks of inactivity confuse the body, causing huge stress on your heart and lungs, which can be life-threatening. Moreover, research shows that it can make you fatter by triggering a process that increases the production of fat cells. With this in mind, here are a few tips to help you to develop a consistent routine.

Start with small, achievable goals

Aim to exercise twice a week for 30-40 minutes, making your heart and lungs work a little harder than is comfortable. This will help you to maintain your current fitness levels, which may not sound like much, but it's a good start.

Upping your workouts to four a week, and to a level where you get hot, sweaty and out of breath, cuts the reduction in your heart fitness between the ages of 30 and 60 to as little as 10-15 per cent as opposed to the usual 30-40 per cent, according to research by the American College of Sports Medicine.

Frequency helps to build confidence

The bigger the gap between training sessions, the greater the sense of trepidation. Aim to be active four days a week, even if two are low-key, such as going for a fast walk in the park for 30 minutes.

Schedule training in your diary

Write down what you plan to do for a week. On each day make a note of what you did, or track it on The Times Health Club, or reaffirm, maybe with a tick, that you completed that day's scheduled task. By clearly structuring your training and having a method of logging your performance, you will stay more motivated.

Treat yourself to a training outfit

Invest in a flattering outfit that you enjoy wearing and get it ready the night before exercising. Rituals are important for psychologically priming you to incorporate exercise into your daily routine.

Remember, it's only exercise

You are not being asked to climb a mountain, swim a sea or fight a war. It's not a punishment. You can adapt your exercise to how you feel on the day. It shouldn't feel as if you are working against yourself. It's worth reminding yourself that you are doing it to be healthier, fitter, slimmer - whatever your goal. Focus on how fantastic you will feel afterwards.

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

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