Effective endurance training is all about stress management, and the balance between stress and recovery. Individual training sessions generate physiological stress – elevations in temperature, heart rate, and stress hormones, changes in pH, depletion of fuel stores, and so on. The stress of individual training sessions is what triggers the adaptive response we look for with training, and this occurs during recovery (1). However, too much physiological stress with inadequate recovery will eventually lead to fatigue, overreaching, and maladaptation, as anyone who has dug themselves a hole with a hard training block can testify.

Therefore, when planning a training programme, and then regulating and monitoring that training programme, we are managing the balance between stress and recovery. We want to ensure there is enough stress to stimulate adaptation, but not so much that we become fatigued, overreached, and burned out. We want to make sure our recovery processes are geared...

I talk a lot about physiological profiling, and how getting tested in an exercise physiology laboratory can be really helpful for refining your training. However, I also know that many athletes do not have access to exercise physiology labs for this testing.

Accordingly, I’ve put together a couple of calculators on the Endure IQ website that you can use to get decent estimates of things like intensity thresholds using easy-to-access field test data.

In this section we are going to talk about the metabolic calculator. I’ll walk you through how to perform the field tests to get the necessary data. But we also include calculators for critical swim speed, functional thresholds power, and critical running speed.

#1: The metabolic calculator

Our first calculator, which you can find here, uses field test estimates of your VLa_max and VO₂max to predict your two lactate thresholds – which we use to determine training zones – and your Fat_max, or the intensity at which...

I talk a lot about physiological profiling, and how getting tested in an exercise physiology laboratory can be really helpful for refining your training. However, I also know that many athletes do not have access to exercise physiology labs for this testing.

Accordingly, I’ve put together a couple of calculators on the Endure IQ website that you can use to get decent estimates of things like intensity thresholds using easy-to-access field test data.

In this section we are going to talk about the critical swim speed calculator. I’ll walk you through how to perform the field tests to get the necessary data. But we also include calculators for fat max/lactate thresholds, functional thresholds power, and critical running speed.

Field test estimate of critical swim speed

The Critical Swim Speed calculator needs to best paced time trials over 200 m and 400 m. This can be done within the same session, so it’s important to have a good warm up before the...

I talk a lot about physiological profiling, and how getting tested in an exercise physiology laboratory can be really helpful for refining your training. However, I also know that many athletes do not have access to exercise physiology labs for this testing.

Accordingly, I’ve put together a couple of calculators on the Endure IQ website that you can use to get decent estimates of things like intensity thresholds using easy-to-access field test data.

In this section we are going to talk about the metabolic calculator. I’ll walk you through how to perform the field tests to get the necessary data. But we also include calculators for fat metabolism/lactate thresholds, critical swim speed and critical running speed.

Field test estimate of cycling functional threshold power (FTP)

If you’re a cycling, you have likely heard of FTP – which is an indicator of the power you can hold for an hour. We can use FTP to generate training zones, and we can estimate FTP using a...

I talk a lot about physiological profiling, and how getting tested in an exercise physiology laboratory can be really helpful for refining your training. However, I also know that many athletes do not have access to exercise physiology labs for this testing.

Accordingly, I’ve put together a couple of calculators on the Endure IQ website that you can use to get decent estimates of things like intensity thresholds using easy-to-access field test data.

In this section we are going to talk about the metabolic calculator. I’ll walk you through how to perform the field tests to get the necessary data. But we also include calculators for fat metabolism/lactate thresholds, critical swim speed and functional threshold power.

Field test estimate of critical run speed: 5-km time trial

Our running field test is a 5-km effort – how fast can you complete 12.5 laps of 400-metre athletics track, although you can also complete the on your favourite flat running route. If...

As you can imagine, I get asked a lot of questions about training. What’s the best type of training to improve VO₂max? How much protein do endurance athletes need? Do I need to do strength training? How early should I taper? These are all great questions, and I love working with athletes to find the answer.

Alongside questions, there are a number of assumptions – or myths – that come up again and again when working with athletes, that I work hard to bust. In this blog, I am going to try and bust six of the biggest endurance sports myths.

Myth #1: Training the gut enhances carbohydrate use.

“I consume carbohydrates at high rates during training, to train my gut to digest and absorb carbohydrates at higher rates. That allows me to get more energy from sports drinks and gels during racing.”

Gut training – the practice of consuming carbohydrates at very high rates during training – has been investigated by researchers. The idea behind gut...

Endurance sport challenges many aspects of our physiology, not least our metabolism and our fuel stores. Our primary energy sources that broken down to power exercise are fat and carbohydrate (1). The body’s fat energy stores are vast and effectively limitless during exercise, while our carbohydrate energy stores – endogenous muscle and liver glycogen – can be depleted to low concentrations during prolonged, vigorous exercise (2–4). Therefore, a vast literature has emerged over the last ~100 years on the importance of our carbohydrate energy stores for endurance performance, and strategies to preserve them, such as through consumption of exogenous carbohydrate in sports drinks and gels. Accordingly, in endurance sport we dedicate a lot of time and effort to planning the optimal dose, type, and timing of carbohydrate ingestion before and during exercise to maximise our performance.

In this blog, we are going to discuss how those of us in performance physiology...

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....

I have been reading and writing a lot about exogenous ketones recently. This is an exciting area of research, and I’m hearing great things from applied practice, too. There’s increasing evidence that exogenous ketone supplements may improve training outcomes (1–4). However, recently as I’m personally not training as much anymore, I have become interested in the use of exogenous ketones from a health perspective. The research is quite fascinating. In this blog, I’ll describe how they might have broader application to health, too.

What are exogenous ketones?

We know that by consuming a diet very low in carbohydrates – less than 50 grams per day or so – we can enter ketosis or increase the circulating concentration of ketones in the blood. That’s why these diets are called ‘ketogenic’ (5, 6). In some instances, such diets are known a “therapeutic ketogenic diets” due to the positive effects they have had on chronic...

I wrote a blog about the recent research assessing the effects of ingesting carbohydrates at very high rates, >120 grams per hour, during endurance exercise (1, 2). My view of the literature, as discussed in the blog, is that there isn’t yet any compelling evidence that ingesting carbohydrates at these super high rates will improve long-distance triathlon performance, or that it’s worth the logistical hassle and risk of gastrointestinal upset. Indeed, there’s even some evidence that carbohydrate ingestion at rates above 90 grams per hour accelerates muscle glycogen depletion and impairs performance (3, 4).

In this blog, inspired by an engaging Twitter thread authored by Prof. Tim Noakes and Iñigo San Millán, I'll delve into the metabolic outcome of ingesting 120 grams of carbohydrates per hour. Through this exploration, I aim to reinforce the...