AS IN so many areas of their lives, too many people who exercise get stuck in the same routine, Amelia Watts, a personal trainer, says. Little benefit is derived from a new physical activity after the first six weeks, by which time the muscles have adapted and need a new challenge.

Make minor adjustments to your routine every four to six weeks, otherwise your fitness will plateau.

EXERCISES: Jack-knife into press-up. Start by rolling over and on to a Swiss ball, so that your hands are on the floor and your feet on the ball. Keep your body in a straight line by drawing in your navel towards your spine. From this position, complete a push-up and then draw your knees into your chest, bringing the Swiss ball in towards you, and then gently roll the ball back out again. Try to complete two sets of 10-15 repetitions.

Press-ups with rotation. Assume the traditional press-up position, placing both hands and feet slightly wider than shoulder-width apart, making sure your fingers face forwards. Lower down towards the floor, keeping your body in a straight line, then extend back to the start position. Tense your core muscles and rotate back so one arm extends up towards the ceiling. Slowly lower your arm back to the floor and repeat 16-20 times, alternating the arm lift.

• Exercises provided by Amelia Watts, of The Tonic, a national network of personal trainers. See www.the-tonic.com or phone 020-8405 1727

  Talk to your GP before embarking on a new exercise regime and do not undertake any activity if you are unwell or injured

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