I am 63 and have been going reg­u­larly to the gym for 15 years. Eight years ago I stopped smoking. Although I have eaten nor­mally since then, I have put on a stone and now have a depress­ing “spare tyre” where my waist used to be. Should I just accept that this is age­ing catch­ing up with me?

As we age, our bod­ies cer­tainly do deteri­or­ate. But that doesn’t mean you have to accept it as inev­it­able: there is ample evid­ence that we can slow or reverse the effects of age­ing with a bit of effort and a smart approach.

Weight gain is almost always down to a com­bin­a­tion of factors. The “spare tyre” is the most com­mon place for the over-​50s to store extra fat – and a stone in eight years rep­res­ents a mod­est increase of 1-​2lb a year, which is argu­ably a “nor­mal” amount to gain just from age­ing.

By middle age, our bod­ies lose muscle stead­ily. This mat­ters a lot because muscle uses more than twice the cal­or­ies of fat, so unless you are also redu­cing your cal­orie intake stead­ily, you will start to gain fat weight. But muscle loss can be reversed if you take up proper weight train­ing (which is also excel­lent for bone health).

Two other factors may also be work­ing against you. Another clas­sic middle-​aged phe­nomenon is “slow­ing down” – basic­ally doing less because we feel more tired and lack­ing in energy. Yet research has shown that if we main­tain high levels of heart fit­ness, we can recover more energy, which allows us to be more act­ive and burn more cal­or­ies. There is a short-​term prob­lem here: espe­cially as an ex-​smoker, you may find it hard work and tir­ing (!) to boost your car­dio fit­ness, but it is worth per­sever­ing for the longer-​term bene­fit.

The third ele­ment that may be work­ing against you is routine. If you have been doing the same thing at the gym for 15 years, your body will have learnt to min­im­ise the effort involved. It really needs a new chal­lenge.

So here are some changes you might make to jolt your body into weight loss and fit­ness gains (depend­ing on whether you have other med­ical con­di­tions that limit your activ­ity – always check with your GP or exer­cise pro­fes­sional).

• Start a ser­i­ous weight-​training pro­gramme. If you do one already, ask a qual­i­fied instructor to over­haul it com­pletely, using dif­fer­ent equip­ment and types of chal­lenge
• Try a new aer­obic (car­dio) activ­ity. Whichever machine you cur­rently use, change to a dif­fer­ent one (or two), and /​or do some swim­ming, join a cir­cuit class, box­er­cise, aquafit, spin­ning or any­thing else that is really going to get your heart pump­ing and your meta­bol­ism mov­ing – three times a week
• Check out your “nor­mal” eat­ing habits. Can you knock out just a couple of things a day that you might not miss but which would save maybe 100–200 cal­or­ies? Typically it might be a mid-​afternoon snack, sug­ary drink or large glass of wine. Go for cut­ting fats out wherever pos­sible, but avoid diet­ing – it is not the answer for you.