Training Diet

Training for three separate disciplines can take up a lot of time and can put a large strain on an athlete’s energy reserves.

As most triathletes train five to seven days a week, often twice a day, it is important that they adopt eating strategies that promote recovery and maximise energy

This can be achieved by following a varied diet that provides:

  • sufficient carbohydrate (CHO) to balance daily fuel needs
  • adequate protein to meet daily needs and assist muscular repair following exercise
  • a variety of fruits and vegetables to promote intake of vitamins and minerals.

About Triathlon 

There are several race distances which can usually be classified into sprint distance (750m swim, 20km bike, 5km run), Olympic distance (1.5km swim, 40km bike, 10km run), half Ironman or 70.3 (1.9 km swim, 90km bike, 21.1km run) and Ironman races (3.8km swim, 180km bike, 42.2 km run).  Races are open to elite as well as age group competitors, with shorter races organised for children.

The type of training undertaken varies according to the level of experience of the athlete, the time of year, and the event.  Typical sessions vary from long aerobic workouts (i.e. 100km cycle) to speed/interval sessions (i.e. track running or heart rate swim sets).  Triathletes participating in long course racing focus more on aerobic type sessions and face unique nutrition challenges in both training and racing compared with short course triathletes.  As a result of these differences this fact sheet will focus on the specific nutrition requirements for triathletes competing in races up to Olympic distance.  Nutrition requirements for long course triathletes are discussed in the Ironman triathlon in later Post.


Carbohydrate – The facts!!

Carbohydrate has received its fair share of bad press. Despite these messages being targeted towards the general public, some endurance athletes have adopted “low carbohydrate” eating strategies.  The truth of the matter is that daily carbohydrate intake should reflect daily activity/exercise load.  On a high activity day additional carbohydrate should be included to meet increased carbohydrate demands whereas on an easy day or rest day, carbohydrate intake should be reduced.

For a triathlete, finding the time to prepare and eat well planned meals and snacks can be almost as demanding as the training itself.  A useful strategy is to have a supply of easily portable nutrient rich snacks to store in your training bag, car or office to meet additional energy needs (e.g. flavoured milk tetra pack, fruit – fresh or tinned, ceral bars, and yoghurt).  Keeping a favourite breakfast cereal at the office is also a good idea, especially if athletes have to go straight from the pool or morning ride to work.

The benefit of having a snack before training or consuming carbohydrate during the training session will be influenced by the goal of the session. Including a pre-training snack is important if it is a quality workout. For instance, if undertaking a heart rate swim set in the morning, having a pre-training snack or consuming carbohydrate during the session (e.g. sports drink) is likely to benefit training performance and ultimately training outcomes. It may be relatively simple to tolerate solid food before going cycling (e.g. banana, toast and jam), however, athletes who struggle to tolerate food before swimming or running may find liquid meal supplements (e.g. Sustagen Sport) before the session or sports drink (e.g. Gatorade) during the session beneficial.

Fluid Needs

The fluid needs of triathletes can be high, especially when training in the summer months. As triathletes may complete more than one session in a day, athletes who do not replace fluid losses incurred during one session may start the next session dehydrated. Triathletes are encouraged to ensure that they have access to suitable fluids before, during and after training sessions.

Triathletes can estimate how much fluid they lose during a training session by weighing themselves before and after training.  For more details see the Fluids in Sport factsheet.

Water should be your first choice fluid although sports drinks may be useful during long training sessions (more than 90 minutes) if training for maximum performance or during competition as they provide electrolytes and carbohydrate for fuel along with the fluid.

Eating before competition

The aim of the pre-event meal is to top up liver glycogen (fuel) stores.  As most triathlon races are held early morning, the pre-event meal should be consumed 2-2.5 hours before the race start and should contain 1-2g of carbohydrate per kg body weight (e.g. a 70kg triathlete should need to aim to have 70-140g carbohydrate in their pre-event meal). It is that the pre-event meal is practiced in training.  Race morning is not the best time to try anything new.   The pre-event meal will take on increasing importance the longer race being attempted.

Examples of pre-event meals include:

  • 1 English muffin with jam/honey
  • 2 medium pancakes with jam/honey + liquid meal supplement (e.g. Up and GoTM)
  • 2 slices of raisin toast + banana
  • Banana and honey sandwich
  • ~ 1-1½ cups of cereal + milk + tinned fruit

Aim to consume 400-600ml of fluid (e.g. water, sports drink, liquid meal supplement) with the pre-event meal to ensure adequate hydration status before the event.  In situations where fluid losses are likely to be high (e.g. very hot races), consume 200-300ml of sports drink or water (or combination of both) 10-15 minutes before the start of the swim, to help promote gastric emptying during the race.

Eating and drinking during competition

During Olympic distance and sprint distance triathlon racing, athletes should aim to consume between 30-60g of carbohydrate each hour.  This can be achieved through a combination of sports drinks, carbohydrate gels and through solid forms of carbohydrate e.g. sports bars or muesli bars. Liquid and gel forms of carbohydrate offer a more practical solution to consuming carbohydrate during racing than solid foods. Regardless of the type of carbohydrate chosen, athletes should practice their preferences during training to avoid unwanted surprises (e.g. gut upset) during the race.

Consuming a sports drink during a race provides fluid and carbohydrate simultaneously.  In Olympic distance races a useful strategy is to have sports drink in one drink bottle and water in the other.  Using two drink bottles is particularly important on hot and/or humid days, when fluid requirements are increased. As an example, an athlete may choose to consume a minimum amount of sports drink (e.g. 300-400ml) and then add extra water to to reflect the environmental conditions. In hot racing, an additional 400-600ml of water may be required whereas in cool racing only 100-300ml may be required.

Carbohydrate gels contain between 20-30g depending on the brand.  There is wide range of options available, with brands varying markedly in taste, texture and composition (e.g. some gels contain extra ingredients such as caffeine).  As they are a very concentrated form of carbohydrate, consuming ~100-150ml of water with a gel is recommended to help avoid any gastrointestinal upset.

At no point should you drink more than your sweat losses during exercise. In longer triathlon events, this can happen, typically for slower athletes competing in cool conditions


After a race, priorities are to replace fluid lost through sweat, replenish muscle glycogen stores and assist muscle repair. Fluids are typically easiest to tolerate straight after the race. A mix of water and sports drink will assist fluid replacement as well as a source of carbohydrate. To assist replenishment of muscle carbohydrate stores foods such as fruit, muesli bars, sports bars or sandwiches are good options. While race organisers will usually provide some drinks, fruit and small snacks for competitors after the race, it cannot be guaranteed that they will have what you need (or feel like eating) so plan ahead. If you have to travel and there is likely a long delay to your next meal options such as liquid meal supplements, flavoured milk drinks, sandwiches and yoghurts are all good examples of carbohydrate containing foods that provide a significant source of protein.

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