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Home / Training / Nutrition / How to avoid weight gain in the triathlon off season

How to avoid weight gain in the triathlon off season

While you undoubtedly deserve a rest and reduction in training, don’t forget to adjust your nutritional intake accordingly this off-season. Renee McGregor explains further…

After months of training and racing, it’s key to let your body rest and recover. While this doesn’t mean a complete stop to training, it may well include a reduced volume and intensity. If nutritional intake isn’t altered accordingly, this’ll lead to a weight increase and an unwanted change in body composition.

One of the difficulties is that the body will have become used to eating a larger volume of food in order to support training, and it can be difficult to reduce this. Weight changes are gradual and so it’s often hard to spot when fluctuations are occurring until it’s too late. Additionally, when you’re working at a high intensity, studies have shown that this can supress appetite rather than increase it, meaning that fundamentally this helps keep your weight in check during the race season.

Personally, I’m very keen on periodising nutrition; this means tailoring your intake to your training. If you’ve adopted this approach, then actually adjusting your intake over the off-season should be a little easier.

Overall portion view

The key strategy for helping maintain weight during the off-season is not to fixate on one food group but to actually look at your portions overall. We know that the only way to maintain weight is to be in energy balance – that is energy in equals energy out. A key thing to know is that this is a balance over several days, not individual days. So when energy output decreases, naturally energy intake also needs to. A common mistake individuals can make is to reduce carbohydrate and nothing else.

While I agree that if you’re not doing high-intensity or high-volume training your intake of carbohydrate should be modified, I’d never recommend reducing it drastically. Carbohydrate is important for immune health: keeping yourself well and boosting your immune system is a further important aspect of the off-season and so I always encourage a moderate intake of carbohydrate a day. Work on the principle of 3g carbs/kg bodyweight a day, or simpler still a fist-size portion of carbohydrate at every meal.

When it comes to protein, I suggest a palm-size portion at all meals and then topping up with 10g protein snacks. Some good examples include: 300ml milk, 2 eggs, 100g Greek style yoghurt, 50g of nuts, 100g edamame beans, 15g beef jerky. Protein, particularly dairy protein, is very useful at reducing satiety, i.e. it’ll keep you fuller for longer and prevent you from raiding the vending machine mid-afternoon.

Don’t forget about essential fats – these too are instrumental in helping your body recover from a tough season as well as boosting immune function. Aim for three servings a day where one serving could be: ½ avocado, 10ml oil – rape/olive, 30g of nuts, 20g seeds or 10g portion nut butter.

What you should eat in abundance is fruit and vegetables – pick an array of colours and variety daily and fill yourself up. This’ll help keep you full due to the high fibre content, but also provide you with important vitamins and minerals.

Boost your immune function

Another significant outcome of a heavy season is surpressed immune function. A heavy training and competition block will take its toll on your immune health and the off-season is when most athletes notice that they become ill. I’ve already mentioned the importance of carbs in maintaining a healthy immune function but some further precautions include:

Taking a vitamin D supplement. In the UK we can only absorb the right wavelength of sunlight to make vitamin D during the months of April to September, between 11am-3pm. Keeping your stores topped up over the winter months is of huge benefit, ensuring your immune health is protected and ready for the new season.

Continue to hydrate. Saliva is your first line of defence. As the weather cools down it can get harder to stay on top of your hydration, once again leaving your immune system exposed to infections.

Rest and sleep. After a busy summer programme, it can be hard to take the rest your body needs in order to recover. But it’s important to build in rest days and ensure that you get at least 8hrs sleep a night. This’ll again benefit your immune system and also allow your body to recover efficiently.

If you tend to be prone to upper respiratory tract infections during the off-season, you’d benefit from taking a 12-week probiotic course.

Try a new sport

My final piece of advice, and it’s not nutritional, is to try a new sport – do some cross training. The body becomes accustomed to the sports it does all the time, using less energy to perform. When you challenge your body, whether that’s with a new weights regimen or a different sport such as climbing, the body has to work hard at learning this skill and actually uses a higher percentage of energy, helping you achieve energy balance.

3 Takeaway Tips

1 Moderate carbs

Keep carbs to a moderate level, aiming for around three fist-size portions a day at mealtimes – choose wholegrains to help satisfy your hunger for longer.

2 Boost your dairy protein intake

Boost your intake of protein, particularly dairy – aim for around four servings a day to help maintain lean muscle mass but also aid satiety so you’re less likely to make poor choices.

3 Eat plenty of fruit and veg

Make sure that vegetables/fruits/salad make up 50% of your intake a day, providing you with dietary fibre and vital vitamins and minerals.

Profile image of Renee McGregor Renee McGregor Sports dietician


Renee McGregor (BSc (hons) PGDIP (DIET) PGCERT(sportsnutr) RD BASES) is a leading sports dietitian, specialising in eating disorders, REDs, The Female Athlete, athlete health and performance. Her practice and knowledge is supported by extensive experience of working in both clinical and performance nutrition, including Olympic (London, 2012), Paralympic (Rio, 2016) and Commonwealth (Queensland, 2018) teams. She is presently working with a number of national governing bodies, including Scottish Gymnastics, The GB 24 hour Running squad, Scottish Ballet, Women’s Reading Football and England National Ballet. She has also provided CPD to The Welsh Institute of Sport and Sports Institute, Northern Ireland. On top of this Renee is the diet lead for global ultra-marathon events series Ultra X, part of the Stylist Strong Women series and an ambassador for Bath MIND Charity. She is regularly asked to work directly with high performing and professional athletes that have developed a dysfunctional relationship with food that's impacting their performance, health and career. No matter who she is working with, whether that’s elite, club-level athletes or those with a dysfunctional relationship with food and training, compassion and care is always central to her practice. She provides a person-centred, holistic approach. She's the best-selling author of Training Food, Fast Fuel books. and Orthorexia, When Healthy Eating Goes Bad. She is the co-founder and director of #TRAINBRAVE a campaign raising the awareness of eating disorders in sport; providing resources and practical strategies to reduce the prevalence. In 2020, in order to increase accessibility to her knowledge and experience she started The Trainbrave Podcast and had over 40,000 downloads in its first year. She is on the REDS advisory board for BASES (The British Association of Sport and Exercise Science) and sits on the International Task Force for Orthorexia. Renee has been invited to speak at several high profile events including The European Eating Disorder Society Annual Conference as the UK expert in Orthorexia, Cheltenham Literature Festival, Cheltenham Science Festival, The Stylist Show and Google. She writes for many national publications and is often asked to comment in the national press. She regularly contributes to radio and TV, including News night and BBC 5 Live. On top of this Renee recently appeared on BBC to support as a diet lead in Freddie Flintoff’s ‘Living with Bulimia’ documentary.