What science says about mixing CrossFit, Hyrox and running to get you ‘clubs’
Traditional weight rooms are changing, and where previously routines divided by muscle groups and the atrocious fear of doing cardio because it “destroys the muscle” reigned, today we have a hybrid training that aims to prevail among all gym lovers. New trend. Disciplines like CrossFitthe explosion of events like Hyrox and the fashion of combining heavy weight lifting with running They have created the figure of the total athlete who leaves nothing aside. But, beyond the marketing that this sports strategy may have, what really happens to our body when we try to be the strongest and the fastest at the same time? A myth. For years, a thought that has been on the minds of many athletes is that running has an “interference effect” with their bodybuilding routines. The reasoning here was that resistance training such as cardio sent molecular signals opposite to strength training, limiting muscle hypertrophy, which is what is sought in the gym. But now there are many nuances about it. For example, an analysis published in 2024 analyzed 59 studies with more than 1,300 participants and pointed out that in women, combining strength and cardio does not produce any interference significant in leg strength. In the case of men, there is a small interference in the development of lower body strength when mixing both modalities, but minimal. That is, it does not justify leaving it aside if we want to improve our health as a priority over hypertrophy. What is the best training? As we have mentioned, hybrid training groups traditional strength exercises with cardiovascular training, such as running on a treadmill. But the reality is that there are many options available, such as Hyrox or CrossFit, and each one has its own peculiarities. Hyrox. A hybrid training that combines 8 kilometers of running interspersed with 8 bodybuilding routines and is often defined as the definitive hybrid test. But here a study from 2025 pointed out that the aerobic factor is the undisputed kingthat is, Hyrox considerably increases people’s aerobic capacity and this is essential to determine the quality of life in old age, since, in addition to cardiorespiratory improvement, it also makes oxidative metabolism more efficient and muscular endurance. Contrary to what many believe when seeing heavy sleds, maximum strength is not a key predictor of success in this competition, but rather it is a systems sport where the entire body is mobilized and makes our cardiovascular system play a leading role. CrossFit. This presents a better metabolic profile, since, by addressing 10 different physical domains, it is postulated as a more complete but less specialized discipline. Here the science indicates that CrossFit dramatically improves cardiorespiratory fitnessoxidative metabolism and muscle resistance. But in addition to all this, it also stands out for the high levels of motivation and adherence thanks to the community component that it has associated. How to do it. If we want to join the hybrid fever, how do we prevent cardio from eating into our strength gains? Here the key seems not to be in stopping training, but in programming each of the steps we take in the gym, since the interference depends directly on the modality, frequency and duration of aerobic exercise. For example, running interferes much more with leg strength than cycling, due to the eccentric muscle damage caused by the stride. One of the most important points here is that, if we want to improve strength over cardiovascular endurance, the best always is to do strength exercises first before starting to run on a treadmill in order to have greater strength gains. When to start. If you want to join this combined exercise fever, the reality is that there is nothing that can stop a person as long as they do not have an injury or a doctor’s recommendation not to do high-intensity exercise. It is true that on the first occasions it may be interesting to go to a personal trainer or a gym where they also have specialists who can develop the best hybrid training plan. And, although this modality is not going to take us to a bodybuilding platform, it does prepare our body for any situation and above all for a much higher quality old age. Images | Alora Griffiths In Xataka | The 11 best apps for exercising at home
