Had a great summer but feeling a tad unhealthy right now? Nutritionist James Collins says the key to finding your healthy feet again is to start a ‘transition period’ (aka ‘time to reign it in’). Susannah Taylor gets on board

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The tan is fading (it did in a week, if you’re honest) as are the memories of watching the sunset over the horizon. As we slowly ease back into work and office life, those multipacks of Magnums that called to you from the freezer, that heatwave rosé, the 'not today' workouts and the lolling about on picnic blankets have all left behind fond memories. They might also have left behind a few extra pounds to. Those black trousers that fitted you perfectly in lockdown are a bit on the tight side. It's not drastic enough to warrant a diet, but a bit of a reset may not be a bad idea.

If this is you right now then you're not alone. Leading Sport and Exercise Nutritionist James Collins says he has many clients that check in with him at this time of year at his practice (The Centre for Health and Human Performance on London’s Harley Street) for just that reason. “They are panicking that they’ve totally fallen off the healthy bandwagon and are not sure how to get back on it,” he says.

Firstly, Collins, who has worked with Team GB Olympic athletes over three Olympic Games, stresses the importance of not beating yourself up about it - we all deserve a break. A specialist in elite sports and exercise nutrition he says he treats his clients as he would his athletes, “We say to athletes, 'Eat, drink and be merry and get loads of rest on holiday.' We actually actively tell them not to keep exercising and eating as they have been - we all need mental and physical recovery.”

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But then how do you break the habits of a wholly unhealthy (but thoroughly good fun) summer? Here is Collins’ advice that should leave you feeling a bit more in control of your body and mind as September starts.

1. Start with a ‘transition week’

Like, possibly, now right after the bank holiday. Collins says in order to find your healthy feet again it’s important to start a transition phase. “This is a week or a short period of time where you start to reign it all in again and start the process to a healthier you.” This way, Collins explains, you aren’t suddenly throwing yourself hell-for-leather into a new health and fitness regime which could be a real shock on both your body and mind and undo the relaxing effects of your summer break.

2. Reintroduce a (gentle) exercise programme

Collins recommends to his athletes to start an exercise programme of some sort. He's not talking five days a week or signing up for Barry’s Hell Week (that's one Barry’s Bootcamp for seven days in a row), but rather a couple of easier workouts for a week or two, whether that’s running, an exercise class or yoga/strength exercises. The aim is to switch your body back on, he says, not to put yourself off for life.

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3. Step away from the snacks

I can vouch for this as a cure for suddenly tighter-than-normal jeans. I remember once having a consultation with nutritional therapist Amelia Freer  and she told me to cut out snacks between meals. While I didn’t really think I ate many snacks, when I shone a spotlight on it, it turned out I did. There were bits of dark chocolate all throughout the day, munching on fruit/cheese/scoops of peanut butter mid-afternoon and general grazing on kids' leftovers. Just a week of being a bit stricter with myself, meant that I could feel my jeans start to loosen again.

“All you need to do is be a bit tighter with your regime and create a slight calorie deficit and you can make significant progress,” says Collins. This means out with the Calippos, chocolate with a cup of tea and to eat three good meals a day. No cordials and sweet drinks (including fruit juices) either says Collins. It’s tough and you might feel a bit hungry, but it works.

4. Rein in the alcohol consumption

A few glasses of vino or cocktails every night may be the norm on holiday and it can be a hard habit to break once home. “You don’t need to go cold turkey,” says Collins, “But if you’ve been having alcohol most nights of the week try going a few nights without. You will feel way more in control in body and mind.”

Not only will alcohol make you sluggish in the morning and less likely to want to work out  but the high sugar content in many alcoholic drinks will end up on your waistline.

5. Start listening to your body again – and don’t be afraid to feel hungry

You may have ignored your body for the last few months, but Collins advises it’s time to start getting in tune with it once more. By this, he means being afraid of feeling a little hungry. We are very accustomed to eating when we feel our stomach beginning to growl, but not feeling full all day is really not a bad thing. “Embracing a bit of hunger is really OK,” he says.

In fact, I have a friend who lost five stone (yes five) and she did it by cutting out all sugar, refined carbs and snacks between meals. She said if she was hungry "so be it" - she knew she'd eat in an hour or so.

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6. Don’t work up an energy deficit

Finally, Collins advises not taking things to the extreme by cutting everything out of your diet and going hard in daily HIIT classes. “I’ve been discussing  ‘Energy Deficiency’ a lot recently,” says Collins (Collins is president of the Royal Society of Medicine’s Food and Health Forum). “Many people are going to extremes and not eating enough then exercising too hard, leaving their energy levels on the floor.” This not only makes you feel atrocious, but it means you can’t do a proper workout (therefore you won’t get the results you need) plus you are more likely to hate every minute and give up everything by September 15th.

"Just because you had a great summer, doesn’t mean you have to have an awful September," says Collins. The key is to be kind to yourself.

Contact James Collins at  jamescollinsnutrition.com   Read  how Susannah Taylor shed 11lbs of post-baby weight with a healthy weight loss plan