Hi, I'm Jo Scott-Dalgleish, a sports nutritionist with a focus on energy management and nutrition for endurance sports. I'm working with Whole Earth peanut butter, official supplier to the British Triathlon Federation, to bring nutritional advice for triathletes on a typical training day ahead of a race.
For a day that includes one to two hours of training, I'd recommend eating three meals and two small snacks. Across the day, you should balance your diet so you consume 20% of your daily calories from protein, 50% from carbohydrates and 30% from fats.
It's important to emphasise carbs in the meal and snack before your training session. If you're training in the middle of the day, breakfast should be very substantial. If you're planning an evening training session, you should make lunch the big one.
Breakfast
Breakfast everyday should combine protein and carbs in order to give your body a sustained energy release that will keep you fuelled for the morning. Porridge with Whole Earth natural peanut butter is a great breakfast.
Then as a mid-morning snack, you might reach for a banana or an apple.
Lunch
A sandwich isn't going to cut it for lunch if you're planning a major training session. I'd recommend rice, vegetables and some chicken. You can buy the ingredients and prepare this yourself or you can buy fresh one-pot meals from a supermarket. You should also have some fruit at lunch time for extra carbs.
An ideal pre-training snack would be oatcakes or a bagel with Whole Earth peanut butter - this will give you the right balance of carbohydrates and protein.
Dinner
Post workout, your main focus should be on protein as the body needs it for muscle growth and repair. You could have 2-3 eggs as an omelette. Or you could have chicken or salmon with a salad. You also need some carbs to replace those burned during training. A major consideration here is ease of preparation as it's often after a training session that lazy habits can arise. It's important not to eat too much too late as you won't be able to fully digest your food and you won't sleep properly.
Things to avoid
I'd always advise avoiding spicy food or a curry before training as this may upset your stomach. You might not normally get an upset tummy from curry, but you might if you run. The spices can aggravate your gut.
In the few days before the race, you should cut down on the fibrous foods, fat and protein that you're taking in - and really emphasise on the carbohydrates in your diet to build up a supply for race day.
Calorie balance
Calorie balancing depends on an individual's metabolic rate and body composition goals.
For most triathletes, in order to maintain your weight, each week you should aim to match the calories you are expending through training. It's almost impossible to do this every day, so a weekly average is the best method.
For someone who is looking to lose body fat and reduce their weight, in order to remain healthy, you shouldn't exceed a negative balance of 200-300 calories per day, or you won't have enough energy to train.
Elite triathletes like the Brownlee brothers train five hours a day and must eat a huge amount of calories just to maintain their weight. If they consumed all those calories and didn't exercise, they'd gain a huge amount of weight!
I hope this helps. Good luck with your training!