Wills and Williamson both use what is called a recurve bow, which bears little resemblance to the traditional image of the bow and arrow.
The draw-weight of Wills' bow is 50 pounds - which means that when he pulls back, a phenomenal amount of tension builds up in the bow.
You have to be strong and have plenty of upper body stamina to keep going for any length of time.
Recurve bows are used in the Olympics but there are also competitive archery events using compound bows, which have pulleys attached at either end.
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