Energy management in triathlon

Energy management in triathlon

One of the key performance factors in any endurance sport is the athlete’s ability to manage the energy at his disposal to keep running, swimming or pedaling at a good pace from the start to the finish line. How do you get a good pace that doesn’t take its toll in the race sector? In this article, we will give some guidelines on how to manage energy in the triathlon cycling sector.

As we know, the biggest component of fatigue in long-distance races is the depletion of glycogen deposits, or in more colloquial terms, the moment when muscles become empty of gasoline. It is at this point that we clearly have to slow down a lot, and this is usually already the case in the foot race sector. The main objective of making a good choice of rhythm in the tests would be to make the arrival at the finish line coincide with the moment when the glycogen deposits are running out, or in other words, to reach the limit.


Heart rate as a reference

This is one of the most frequently asked questions for coaches: how many beats do I have to go to on a bike in order not to pass and be able to run in conditions? The question is very good, and the answer is not very easy, because when we talk about heart rate we must not forget that although it is a very useful intensity meter is also affected by some variables that can alter a little the usual values. Fatigue, dehydration, temperature, the emotion of the moment or caffeine cause changes in the heart rate that can confuse the triathlete in a way the day of the test. Even so, and with these limitations, the heart rate can be a valid reference to regulate the intensity in triathlon when a watt meter is not available, which as we will see later is a more precise tool for these needs.

For practical purposes, our reference in heart rate is what we call threshold heart rate, which is the maximum heart rate we can hold for one hour. It can be estimated with an error of 2-3 pulsations doing a test of 20 minutes to top multiplying the result by 0.98. We can also estimate the heart rate threshold if in some training we have squeezed to the top or if we have done some cycling race. It is important to point out that the FC threshold on a bike is always lower than the one we have running on foot, so it is necessary to have the data for each sport. Let’s see in which pulse ranges zones we should be when we are going to do a competition:

Olympic triathlon with drafting. When we talk about races in which we can go to wheel of other cyclists the importance of regulating based on pulsations passes to a second plane, since the most intelligent thing is to try to go in some group. And when we go in a group, the rhythm is what it is, let’s say we can’t choose. We say that the most interesting thing is to go in a group because the aerodynamic benefit of going to wheel is going to allow us to save a lot of energy for the foot race sector. However, it is important to have a reference in case we are left alone or if there is a lot of climbing where groups tend to break up. The idea for triathletes with medium-high level is that the pulsations are between the threshold and five pulsations below. In the case of triathletes with less experience, it is recommended to be a little more conservative and move between 5 and 15 beats below the threshold. These references can be very useful for triathletes who are very good swimmers in relation to their abilities as cyclists, as they run the risk of over-intensity if they try to follow the cyclists who are clearly better on the bike. If we are faced with the opposite case, a triathlete who is a bad swimmer and a good cyclist, the heart rate references mentioned above can serve as a reference if we are clearly faster than the cyclists with whom we get out of the water and we have no choice but to go up. For strategic purposes, we think it is important to insist on the advantages of going to the wheel of other cyclists whenever possible, so if at some point in the test we are alone in a long flat stretch the best is to slow down a little and wait for a group to reach us.

Olympic triathlon without drafting. When we can not go to wheel is when it becomes more important the ability of the triathlete to regulate the intensity at which he will pedal to make a good partial bike that does not penalize him in the speed of the race. In this case, we return to the references above: for triathletes with medium-high level the idea is that the pulsations are between the threshold and five pulsations below. In the case of less experienced triathletes, it is recommended to be a little more conservative and moves between 5 and 15 beats below the threshold.

Medium distance. As the competition lengthens, the degree of energy fatigue is greater, and therefore, more chances are there to be wrong with the pace of competition. When we have to deal with a 90-kilometre bike sector, our reference in pulsations should be between 20 and 10 pulsations below the threshold. The less level we have or the more conservative we want to be, the closer we get to 20 beats below than 10.

Long-distance. It is clear that to then run a marathon what we do on the bike is going to be very decisive. The need to make a good strategy with the pace of the bicycle sector is crucial. In this respect, there are two publications in which he recorded the heart rate of two groups of high-level triathletes during an Ironman. In both studies, the average heart rate was 146 beats. This HR was associated with a fairly accurate heart rate corresponding to the ventilatory threshold. In this case, we are talking about high-level triathletes (VO2max of more than 65ml/kg/min) whose rhythm we can say is high compared to what we can expect from a triathlete who participates in age groups, more than anything because the duration of his test is shorter and because his metabolism of fat intake is more optimized. If we talk about references to the anaerobic threshold mentioned above, we can say that the triathletes with the highest level perform the cycling sector between 25 and 30 pulsations below their anaerobic threshold. For a medium level triathlete, the recommendation would be to be around 30-40 pulsations below.


The utility of the power meter

As is well known, the use of power meters is increasingly widespread among cyclists and triathletes, as the ability to measure the work done adds a lot of information in the process of training and assessment of physical condition. In addition, it can be a very useful tool to regulate the intensity in triathlon as we will see now since the power at which we are able to pedal is a more constant and reliable measurement than pulsations. They are not really comparable, as they measure totally different things. Pulsations are a physiological manifestation of the physiological stress to which we are subjecting our body (intensity of pedalling, temperature, fatigue, emotions…), and the power at which we pedal is simply a measurement of the work we are capable of doing. Let’s see how we can use it in competition, although first of all we will make it clear that we are always going to refer to values of normalized power, not average power, as it is a more accurate meter of intensity. In previous issues of Sportraining, we have already explained what the normalized power is.

Olympic triathlon with drafting. As we have already pointed out when we were talking about heart rate, rhythm management in these short-distance events is mainly marked by the strategy of the race, that is, by the group in which we go. In this context, it is not very useful to use the power meter during the race but to analyze, a posteriori, the watts at which the race has been disputed. Based on personal data, we know that at the elite level the sprint distance is disputed at an intensity between 95 and 100% of the functional threshold of the triathlete, going down to 90% in the case of popular triathletes.

Olympic triathlon without drafting. When it is not allowed to go to wheel, the wattmeter can be a useful and valid reference to regulate the intensity of pedaling in Olympic distance being the reference between 90 and 95% of the functional threshold for popular triathletes and between 95 and 100% for the triathletes of more level.

Medium distance. As we increase kilometers, the utility of the wattmeter is greater, since energy management is a little more complex. Here there begin to be quite a few differences between the rhythm that a beginner triathlete is able to maintain in relation to an experienced elite. For a beginner and being conservative, we should look for an intensity between 70 and 75% of the functional threshold in medium distance.

In triathletes with more experience and level of physical condition can be forced more, approximately between 75 and 85% of the threshold. The elite reaches up to 90% of the functional threshold.

Long distance. As is logical, to face 180km and a marathon the pace must be lower. In this case, for novice triathletes in the distance, it is recommended to maintain a rhythm between 65 and 70% of the functional threshold. Those athletes with more experience can go a little further and be between 70 and 75%. The professional triathletes reach 180km at 80% of their threshold as the most intense reference.

Experience is a key factor


In medium and long-distance, the experience is a very important factor when it comes to knowing exactly what intensity we are capable of making the bike depending on the sensations or performance we have had running.

Good advice for the less experienced triathletes is that within the recommended intensities they should be conservative in their first races. In other words, if this is the first time that we are doing Ironman distance, it would be better to look for an intensity between close to 65% of the UF than to go from first to close to 70%.

Running the marathon at an acceptable pace without great hardship is going to make this first experience much better, and this is achieved, in part, thanks to having done proper management of the intensity on the bike.