Actuary 400m, my upcoming book goes into some detail on this (relative to the work of Zhelyaskov and Dasheva of the National Sports Academy in Sofia Bulgaria) and other topics so I wont reiterate here. what I will do is give you a simple overview of one way, as simplified as it is, to conceptualize power vs capacity as it pertains to any bioenergetic domain:
Power = peak intensity
Capacity = total work output
while the contribution of all systems are present in nearly all activities, think of the thresholds (between alactic and lactic and aerobic) that separate the predominance of each system’s contribution to a particular task.
At any given intensity/duration of a particular task, you must think of the barometer by which you are measuring intensity. In running/sprinting, velocity prevails in my view because the highest velocities always equate to the winner in any race. Even in the middle and long distance races, when the pack goes out slow, it’s the runners with the most speed who are the dangers to the rest when they kick it out. Alternatively, a blazing fast pace, such as what Rudisha laid down in London 2012, was achievable due to his ability to achieve and sustain such a great velocity for the given distance. All the way to the marathon in which Kimetto’s ridiculously fast average mile pace of 4:41 over 26.2 miles.
The context then becomes whether the discipline is more a factor of power or capacity and this is generally where the thresholds between the systems come into play. The highest sprint/running velocities are always achieved within the power (near the threshold of capacity) of the respective bioenergetic system. In the short sprints its a function of maximum velocity and speed endurance and in the middle and long distance events it’s a function of speed at the anaerobic threshold.
Pierre Jean Vazel provided a fantastic statistical break down, as usual, of Van Niekerk’s 400m WR (I’d post the link, however, Angela has prohibited the posting of links to other sites)
0-100 in 10.7
100-200 in 9.8
200-300 in 10.5
300-400 in 12.0
Niekerk’s fantastic speed reserve coupled with his aerobic qualities are the perfect storm for the 400m event.
As the topic relates to continuous cyclical efforts (sprinting, cycling, rowing, swimming, skating, Nordic skiing…), dedicated efforts to go as fast as possible from point A to point B in which point B is shifted to longer and longer displacements away from the start, any athlete will transition through the continuum of alactic power to alactic capacity to lactic power to lactic capacity to aerobic power to aerobic capacity, with the proportion/contribution depending on the distance.
In the 400m, it’s matter of determining what must be done to maximize velocity throughout. Each athlete’s physiology yields a different formula; however, at the end of the day there is no refuting the fact that the sprinter with the smallest sum of adding 100m splits wins the race. The question is how to get there and due to physiological differences, there cannot be one single answer.