I don’t intend to discover a magic potion<\/a> or any secret formula regarding sports performance. In many cases, what you read will reinforce what you’re already doing. In others, it might help you introduce adjustments that make your sessions more efficient. It’s also not about questioning the work of other professionals: sports performance can be achieved through different paths. I’ll talk about what I understand works for me. <\/p>\n While I receive suggestions on specific topics -I encourage you to send them in the comments-, I’ll start by answering a fundamental question:<\/p>\n We could find multiple answers, approaches, and nuances when addressing the question of what factors sports performance depends on. However, from my point of view, success in sports training is mainly based on two major pillars: <\/p>\n In this first series, we’ll focus on the former.<\/p>\n If we’re talking about improving our sports performance at a specific distance, it’s clear that the needs of a 5K aren’t the same as those of a marathon.<\/p>\n Physiological demands fundamentally depend on one factor: the duration of the effort.<\/strong><\/p>\n To the point that, in terms of energy metabolism, a cyclist looking to break the hour record will use similar metabolic pathways to those of a half-marathon specialist, as both efforts last around 60 minutes.<\/p>\n In other words, different disciplines can share similar energy requirements if the effort time is comparable.<\/p>\n If you search for the term \u201cenergy system contributions\u201d<\/em> you’ll find plenty of scientific literature analyzing how different energy systems contribute depending on the duration and intensity of the exercise. That’s what I did back in the day to develop the theoretical framework for my doctoral thesis<\/strong><\/a>. <\/p>\n To put it simply, our body has three major energy production systems:<\/p>\n In endurance races, the aerobic system plays a clear leading role. However, the other systems don’t disappear: they contribute at specific moments like changes of pace, short climbs, or final sprints. <\/p>\n We can imagine the body as a vehicle with several fuel tanks.<\/p>\n Training seeks to optimize:<\/p>\n If we use all the “tanks” at maximum intensity from the start, we’ll only be able to sustain that effort for a limited period. Afterward, fatigue will appear prematurely and performance will drop. Therefore, that strategy only makes sense for short-duration endurance races (middle-distance<\/em>). <\/p>\n On the other hand, if we properly manage which energy system predominates at each moment, we can sustain performance for longer.<\/p>\n In long-duration road races, we usually look for flat routes to optimize the final time. But why does this happen? <\/p>\n A flat route allows for a more stable intensity, which favors greater efficiency of the aerobic system.<\/p>\n In contrast, in trail running or cross-country races:<\/p>\n This implies that, even while maintaining the same total duration, the relative contribution of energy systems changes according to the terrain.<\/p>\n When we combine:<\/p>\n An essential concept in endurance performance appears:<\/p>\n Pacing<\/em> isn’t just “starting slower”; it’s the ability to strategically distribute effort to: <\/p>\n We could say that poor pacing<\/em> involves prematurely activating less efficient energy systems for prolonged efforts.<\/p>\n Good pacing<\/em> means understanding what the race requires and adapting the energy strategy from the very first kilometer.<\/p>\n In the next series<\/em>, we’ll address this concept in depth and connect it with energy contribution systems.<\/p>\n Sports performance doesn’t just depend on training more or training harder.<\/p>\n In reality, it depends on understanding the following:<\/p>\nWhat factors does sports performance depend on?<\/h2>\n
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Series 1: Energy System Contributions<\/h3>\n
The race determines the physiological demands<\/h4>\n
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<\/a><\/p>\nWhat energy systems are and why they matter<\/h3>\n
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<\/a><\/p>\nThe fuel tank analogy<\/h3>\n
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The route also modifies energy demands<\/h3>\n
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<\/a>Duration + route profile = strategy<\/h3>\n
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Pacing (rhythm distribution)<\/h3>\n
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![\"Pacing](\"https:\/\/42krunning.com\/wp-content\/uploads\/2025\/06\/jornada-42k-00044-scaled.jpg\")
<\/a>Conclusion: understand before intervening<\/h3>\n
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