Edited by Francesco Calise
Many of us use this term every day in the most diverse fields and applications. It is obvious what an individual wants to represent when he states that an athlete rather than a car or any other type of machinery is more or less powerful.
In reality this term expresses a rigorous mechanical concept from which obviously the man machine cannot ignore either, with all the implications that we will see on energy metabolisms.
To understand this concept we will take a step back by first analyzing strength and then work.
Sports literature defines strength as "Man's ability to oppose or overcome resistance by muscular effort (Zaciorskji)". According to the general principles of mechanics, the force measurement unit is expressed in Newtons, which take into account the gravitational force acting on the body under examination. For example, if an object has a mass of five kg, the force that it will be able to exercise will be around fifty Newtons (50N). To return to a concept close to us if I want to support a weight of five kilograms in my hand (to oppose a resistance of 50 N), I will have to contract my biceps with such a force that it allows my forearm to remain immobile at the chosen angle of the elbow. The principle of the levers and of the "moment of strength" comes into play here, but we will not analyze them.
Mechanically the work is expressed with the formula:
W = F xl
Where W is the work, F is the force and l represents the distance in which this force is operative. Let's try to clarify with an example:
If I lift an object that weighs ten kilograms to place it on a table one meter high, I will have developed a work (muscle) of one hundred Newton-meters (100 Nm).
It seems clearer to me this way, doesn't it?
As we have seen, force expresses a static concept, work adds the space factor and if we add the time factor we will finally get the mechanical principle of power . It is equivalent to the work performed ( W ) in the unit of time ( t ). From which the formula:
P = W / t
The unit of measurement of the work is the Nm, that of time is the second, it follows that the power is measured in Nm / so with a measure universally known as Watt (W). Yes, those of the bulbs, of the exercise room bikes or those on which we calculate the car tax!
If we reflect for a moment on the formula of the work we note that we can rewrite the formula of power in this way:
P = F xl / t
We all know that space / time ( l / t) is the expression of speed ( V )
Ultimately we can represent power as:
P = F x V
From this formula we can deduce the key to the increase in performance in every sport:
To increase power or increase strength or speed.
Of a disarming banality!
Whenever force and speed are related, we will evaluate power expressions that will differ depending on whether the latter is more oriented towards the first or second quality mentioned above.
Every sport requires its own type of force, generally defined as a special force; each athlete will therefore have to try to reach the optimal level of strength specific to the discipline he practices.
This concept is expressed graphically according to the Hill curve which represents the "fundamental equation of muscular dynamics" (Hill, 1938). In short, it highlights the inverse relationship between strength and speed.
In the specific case of indoor cycling the type of force required will be of two types:
- linear aerobic strength
- linear anaerobic force
The energetic mechanisms mainly involved are those of oxidation and glycogen (anaerobic alactacid), almost never that of phosphagene, used exclusively for rapid and explosive gestures with a maximum duration of 6/8 seconds. In our discipline they could be assimilated to short and occasional sprints.
It is clear from what has been said that the best thing to do to improve the aforementioned specific qualities is to foresee during the year a periodization of training to be able to work in a targeted manner on the most advantageous qualities for us pedal lovers.
