Answer:
From my point of view, the most strenuous activity on the list would be swimming. It is a complete activity that involves the majority of the muscles in our body and stamina to swim long distances in short periods. Due to these two factors, it requires high amounts of energy. All the previously mentioned characteristics about swimming make this sport a very strenuous one.
Explanation:
Swimming is a strenuous sport since the muscles in our body are constantly working to move our body from one end of the pool to the other or to reach a point in open waters. Also if we want to float we have to move our muscles to not sink. We can see that while we swim, we are using our muscles for long perids of times wich may not happen in sports such as football or badscketball were we mostly use certain muscles' groups and for shorter periords.
The constant movement requeries stamina to reach longer distances as we improve over time. Long distances in swimming can be extremely challenging, in addition with the coordination of breathing and the right movement of our limbs, which demands high levels of concentration.
Lastly, the stamina, the majority of our muscles' involvement, the distances, and speed demands considerable amounts of energy. All these factors together make swimming a strenuous activity.
