“If you’re out for a training session that’s longer than an hour, make sure you’re thinking about your fueling during it. I typically use isotonic gels. I take them every 30 to 35 minutes during a long run.
“Don’t do any training fasted. I know that’s a big thing because people talk about training their body to run on fat but when you wake up, your cortisol levels, which are your stress levels, are at their highest. So if you go out with no food to do exercise, which is fundamentally stress on the body, you’re putting stress into your body. Fueling takes some of that away and helps with energy levels and recovery.
“Where it might vary is for someone who doesn’t train a lot and they’re limited for time and they’re going out for a short, easy run—then you can do it fasted. However, I think if you’re following a training plan and you’re an active person, plus you’ve got a busy job, a lot on your plate, and your sleep is not optimal, then definitely avoid that fasted training.
“Fueling afterwards requires focus. It’s more important for people who do a lot of training. Be conscious about that refueling because it helps with your recovery, which will then have an impact on the next session.
“Try for a balanced diet. If you’re someone who perhaps struggles to keep to a certain weight, then it’s about being balanced with what you eat. We’re usually aware of what makes us put on weight, but when you’re training, be aware that you need fuel. Don’t starve yourself.”