The answer is one which is hotly debated, much hypothesized yet little understood. That athletes consistently finish races with a ‘kick’ – what is also referred to as the ‘endspurt’ – is as universal as it is cliché. When pacing is of the utmost importance – as in triathlons of varying distances, TTs or hill climbs in cycling, and all running and swimming races – it is both critical to not start out too fast but also ensure we’re not holding too much in reserve. The “Science of Sport” site speaks of Haile Gebrselassie’s world record 10k of 26:22.75 from 1998. His final kilometer of that race was 2:31.3, compared to 2:37-2:38 for the previous 9km. The point being that even the most elite athletes follow a similar ‘kick’ strategy as the fastest age groupers, middle of the pack racers as well as less experienced beginners.
It’s obvious athletes speed up at the end of races. But, why? Why not race faster sooner? Some say this is a stupid question because the answer is so obvious. “If athletes ran faster sooner, they would slow way down or maybe not even finish the race.” Or, some variation of this answer. No kidding. If I’m running a 10km, then I’m not going to start the race as fast as if I were running a 1-mile race. But, this is not what’s being asked. Rather, why didn’t Gebrselassie run 2:34-2:35 per kilometer straight across and, thus, finish with an even faster time?
The hypotheses (these are not theories; they are unproven) to explain this phenomenon are quite diverse. One idea is that training and experience teach athletes about their limits and, therefore, they inherently know how to best pace an event. But, based on what information, what inputs, what outputs? How can you really compare a race today to one you did months ago as far as how you feel now versus felt then? And, if athletes simply decide to slow down, is that a rational process? In other words, do athletes literally decide to slow down because if they don’t then they know they will be in trouble later in the race? How would athletes know this? Experience? The question to ask is multi-dimensional: What cues, what signals, what experiences, what training and what physiology are responsible for enabling athletes to consciously slow down just enough during a race and then speed up at the end to still maximize performance? Athletes have to balance the requirements of the race at every point during the race to avoid any limit to optimal performance. Your pacing strategy is the output and that output is based on countless inputs – experiences both positive and negative, training, diet, altitude, temperature, energy and even something like deception; effectively, can we trust ourselves?
Another is that athletes slow down as their calcium channels become more and more ‘leaky’. As we fatigue, we utilize calcium to help keep muscle contractions forceful. As we use, or leak, that calcium, the force of the muscle contractions goes down so we cannot perform as well. Muscles are unable to exert their normal force. But, what about the hypothesis that as we fatigue we start to recruit more and more muscle fibers to counteract this mounting fatigue? And, how can an athlete even be remotely aware of ‘leaky calcium’, something that occurs down at the cellular level? Wouldn’t an athlete need to know this was going on as part of being able to more intelligently pace his/her race?
The hypotheticals go on and on. The two mentioned above just typify the arguments. To me, what it all boils down to is this. Regardless of WHY it happens, the effect of any voluntary effort is that some amount of something is held in reserve – regardless of how hard we try. Maximal efforts are capped at 5 seconds in duration. Athletes can try as hard as they possibly can for those handful of seconds and, yet, it is still a submaximal effort. We know this because when subjects are hooked up to an electric current during their maximal efforts, the force the working muscle is able to exert goes up. So, clearly, when athletes think they are ‘giving their all,’ they are not.
This is a survival mechanism hard-wired in the body. The body holds something back to keep us from literally killing ourselves through overexertion. It is this reserve which athletes dip into to achieve that ‘finishing kick.’ We have probably all experienced this. We are ‘on the rivet’, at our physical limitations, yet we find a way to ‘dig deeper’ and pull just a little more out of ourselves. We drive ourselves to the point of collapse, and sometimes we do indeed collapse. In some cases, the collapse is fatal.
There is so much going on within the body at any given time that is would be impossible to determine precisely why all this occurs. Suffice it to say that we KNOW it occurs, but anyone who tells you WHY it occurs is lying. For example, athletes slow down as the body heats up because the brain’s ability to activate the required muscles starts to fail until they can no longer continue exercising. But, WHY? And, why when our brains are limiting output can we then override the survival mechanism to then access our energy reserve?
Hopefully you’re learning some stuff here. There are no clear cut answers, nor is there even any one thing to point to as the lynch pin of all this. But here’s what I can promise. The next frontier for accelerating human performance won’t come from better training techniques or improved technology and equipment. Rather, it will come from figuring out how to increase our access to and control over our brain power. Even an infinitesimal uptick would result in a multi-percentage increase in performance. And, since the best athletes in a given sport are only separated by less than 1% in output, the ability to gain several percentage points in performance is, quite literally, a game changer.