With the athlete I coach, I promote what I call the “Right Fuel, Right Time” approach to nutrition for endurance training, as discussed in blogs and on our courses. By "Right Fuel, Right Time," I mean advocating for the timely management and adaptation of nutrition, particularly carbohydrate intake, according to training demands. These objectives may aim to maximize acute performance within the session or facilitate high rates of fat oxidation.

In the literature, we come across the term "Periodised carbohydrate intake," which is an approach that follows a very similar principle and is seeing increasing research interest (1, 3).

The rationale for this approach is that adequate carbohydrate should be consumed to support the quality of training sessions. However, we should avoid over-consuming carbohydrates on easier, less demanding days, as this may blunt the signals that lead to positive adaptive responses (2). Carbohydrates and fats are the body’s primary fuels. While fat stores are ...

It’s Monday, and we’re fresh from some great racing at Ironman New Zealand. It was really great to be down watching some racing again (and yes, I did miss racing myself!).

While down at the event, Prof Grant Schofield and I were invited to present on the low carbohydrate healthy fat (LCHF) performance for Ironman.

The link to the presentation can be found in this closed Facebook group here (anyone can join), and we think it was quite well received with 50+ people attending.

However, as always around racing, one of the main questions we always receive is “how do I fuel my races with LCHF?”. Luckily, along with two of my endurance physiology colleagues at AUT, we discussed this very topic in a paper that used theoretical energy fuel requirements of Ironman triathletes at different performance levels (~8 h, ~9 h, and ~13 h).

This paper was published in the Journal of Sports Medicine, and I’ve tried to summarise below. The science is quite heavy so I will split this blog into two parts...