Can My Growth Spurt Make Me Faster Than Usain Bolt?

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Discussion Overview

The discussion centers around the relationship between growth spurts, height, muscle mass, and running speed, specifically in the context of whether an increase in height could lead to faster sprinting times compared to Usain Bolt. Participants explore the implications of physical growth on athletic performance, including theoretical calculations and physiological considerations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant shares their current running time and height, speculating that their speed might increase with their predicted growth in height and muscle mass.
  • Another participant questions the assumption that speed would grow with the cube of height, prompting a discussion on the validity of the calculations presented.
  • Several participants highlight the need for a sanity check on the predicted times, suggesting that the calculations may not logically follow from the initial running performance.
  • There is a discussion about the relationship between muscle mass and strength, noting that increases in muscle mass do not directly translate to proportional increases in strength.
  • One participant emphasizes that speed is not solely dependent on muscle strength, mentioning factors such as oxygen storage and fuel processing during running.
  • Another participant points out that mass can limit speed due to inertia, complicating the relationship between muscle mass and running performance.

Areas of Agreement / Disagreement

Participants express differing views on the calculations and assumptions regarding speed and growth. There is no consensus on the validity of the proposed relationships between height, muscle mass, and running speed, indicating an unresolved discussion.

Contextual Notes

Participants acknowledge limitations in their calculations and assumptions, particularly regarding the relationship between height, muscle mass, strength, and speed. The discussion reflects a range of perspectives on these complex physiological interactions.

Who May Find This Useful

This discussion may be of interest to individuals exploring the effects of physical growth on athletic performance, as well as those curious about the biomechanics of running and the relationship between muscle mass and speed.

Gus Timmer
I ran 60 meters in 8,53 seconds today, but the thing is, I don't work out, I just started my growth spurt (I'm 160cm tall now but my doctor predicted I'll grow to be 185cm tall) and my body fat percentage is probably near 15%.
I calculated what nu speed would be if I was 185cm talk but without taking into effect gravity and other factors like that
185/160=1,15625
1,15625^3=1,54580688476562
60/8,53=7,0339765533411 m/s (average speed 60m)
7,03397655411*1,54580688476562=
10,8732020030407m/s (average speed at 185cm)
100/10,8732020030407=
9,19692285419096s (on 100m at 185cm)

I don't expect these calculations to be correct so I'm asking you.
My weight is 47kg at the moment if that is tot any relevance
 
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Gus Timmer said:
1,15625^3
Why do you think your speed will grow with the cube of your height?
 
Let's look at this, not your calculations:
60 meters in 8,53
is your time for 60m. Correct? You predict 9.19s.

so:
Code: 
9.19 - 8.53 =  .66
Therefore you would have to run the last 40m in .66 seconds, whereas you the previous 60m in more than 8 seconds. Or, you would have to the last 40m about sixteen times faster than you did the first 60m. Sound logical to you?

It is useful to do a sanity check on your result before worrying about anything else.
 
As I said, I don't expect my calculations to be correct but I figured my speed would increase alongside my muscle mass.
 
jim mcnamara said:
Let's look at this, not your calculations: is your time for 60m. Correct? You predict 9.19s.

so:
Code: 
9.19 - 8.53 =  .66
Therefore you would have to run the last 40m in .66 seconds, whereas you the previous 60m in more than 8 seconds. Or, you would have to the last 40m about sixteen times faster than you did the first 60m. Sound logical to you?

It is useful to do a sanity check on your result before worrying about anything else.

I don't think I am faster than Usain bolt as of now, I think I can be faster when I am 185cm tall
 
Well, you would have to be 10X times taller... using your approach. It still says that you would have to find a way to go faster by a large factor, and growing another 15% of height won't do it. @A.T. pointed out some issues for you. I'm suggesting that in general, a critical look at a result can give you an idea if you are in the correct ball park to start with. Your time with your new future height would need to be ~5.7s for 60m as a rough guess.
 
Gus Timmer said:
As I said, I don't expect my calculations to be correct but I figured my speed would increase alongside my muscle mass.

Not quite. Muscle mass increases directly proportionally to the volume of your muscle. But muscle strength only increases proportionally to the cross sectional area of the muscle. As you grow, your muscles increase in both length and width, but the volume (and thus mass) increases faster than the cross sectional area. So if your muscle mass doubles, you aren't doubling your strength. At best, I'd expect perhaps a 1.5x increase in your strength, but I haven't done any detailed calculations. It could be a little more, or a lot less.

In addition, speed isn't directly proportional to muscle strength. I can do squats and other leg exercises to increase my leg strength, but my speed will have only a marginal increase, if any.

And if that weren't enough, we'd also have to include the fact that your muscles require oxygen and fuel to burn as you run that 100 meters. Your body can't provide enough of either of these as you run (which is why you tire out), so your muscles have to store some of this to use when needed. So average speed over some distance also depends on your muscles ability to store and process this oxygen and fuel. But I don't know how much they can store and I don't know how it increases with different types of exercises.

Long story short, this is a complicated topic and simply calculating muscle mass/strength won't do you much good.
 
Gus Timmer said:
I figured my speed would increase alongside my muscle mass.
Mass means inertia, which limits how fast you can swing your legs, while muscle strength depends on crosssection.
 
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