When I star­ted a fit­ness régime last month I was full of determ­in­a­tion. I am at my local gym three times a week, with a brisk hour-​long walk at the week­end. I am eat­ing sens­ibly, no alco­hol etc. Yet I put on 2lb in the past fort­night. I know it’s silly to get dis­cour­aged this soon, but am I doing some­thing wrong?

There are sev­eral pos­sible explan­a­tions for your appar­ent weight gain, mostly to do with the daily fluc­tu­ations that nearly all of us exper­i­ence. Weight can go up or down by a pound or two from day to day, whether or not we are on a diet. These vari­ations can be down to eas­ily over­looked factors, such as using dif­fer­ent sets of scales, or even mov­ing your own scales from bath­room to bed­room; or wear­ing dif­fer­ent cloth­ing /​shoes for your weigh-​ins.

Equally vari­able but less obvi­ous are factors such as the time of day you weigh your­self, how hydrated your body is, whether you’ve recently eaten a meal or even drunk a buck­et­ful of cola at the cinema. Many women suf­fer from water reten­tion before a period, which also affects weight.

So your 2lb “gain” might be down to any of these subtle vari­ations, none of which has any­thing to do with your healthy life­style régime. If you are going to do reg­u­lar weight checks, I sug­gest you restrict them to no more than twice a week, using the same scales in the same place each time – and prefer­ably make this first thing in the morn­ing with no clothes on. That way, you can limit some of the mis­lead­ing fluc­tu­ations, and avoid becom­ing obsessed (or dis­ap­poin­ted) by the res­ults of a daily weigh-​in.

Having said this, there is one haz­ard you need to watch out for. You say you are eat­ing “sens­ibly”, which sug­gests you have not gone on a diet as such. This is fine. The level of exer­cise you are doing is great and you should already be start­ing to feel health­ier and fit­ter. But it’s quite com­mon for people to make an almost sub­con­scious adjust­ment for increased activ­ity by allow­ing them­selves just a bit more of what they fancy as a sort of reward for their good work.

Even if you are eat­ing more sens­ibly, you need to ensure that you have not star­ted to increase the por­tions, or slipped in a chocol­ate treat or two each day, which you then men­tally write off against the extra exer­cise you are doing. Remember: the bot­tom line to los­ing weight is that you have to eat fewer cal­or­ies than you are burn­ing on any given day. It is likely that prior to your life­style change you were slightly over-​eating on a daily basis, which is what causes the weight to creep on in the first place. So you need to keep a tight rein on cal­or­ies eaten in order for all that extra effort to show up as weight loss.

Steel your­self for good weeks and some no-​progress weeks, and keep your sights firmly on a six-​month goal: you’ll be delighted when you real­ise you’ve made it!