Arm Strength/Size

[rainy.here]

@teabagallday

Elite sprinters tend to have very muscular/large arms and sprint programs generally include an emphasis on increasing arm strength. I was wondering what the exact effects were from arm strengthening. Does arm strength alone actually make a person run faster, or does it simply allow them to make use of more leg force? And is having a large upper body beneficial, or is strength the key with upper body training? Thanks

If someone with weak arms runs a 200m, their arms will be extremely fatigued by the end.