Difference in speed; head above water and head under water.
Former Member
I have folowed a lifeguard course and we always had to swim with our head above water.
2 requirements for the exam were:
- From the side jumping into the water, one lap entirely under water, 2 25 meter laps on back with arms above water (to prove that the kick is efficient enough) within 100 seconds.
- 200 meters in 4 minutes and 15 seconds (which is even quite doable with the breaststroke), of course with head above water.
At the university swimming pool I noticed a list for the sportmasterstudents (they study sport at an academic level) with required times and laps.
This got me wondering. How much faster can you swim a lap when you swim with your head under water compared to when you swim with your had above water?
I suspect that the relative difference in speed will be larger for a sprint than for an long distance.
Parents
Former Member
Unless you're a fish, pulling and kicking with our appendages provide the lift and drag forces which are the most important propelling forces for humans as they swim. Swimming underwater is slower for many reasons, the recovery stroke underwater slows you down compared to above water. The inability to effectively use your hands is also a negative when comparing the two. The dolfin kick is extremely effective underwater but without the use of the arms, the dolfin kick cannot compete with the butterfly done above the water. I hope that answers your question.
There may be a few weird rebuttals but they'd only be weird. Good luck.
Unless you're a fish, pulling and kicking with our appendages provide the lift and drag forces which are the most important propelling forces for humans as they swim. Swimming underwater is slower for many reasons, the recovery stroke underwater slows you down compared to above water. The inability to effectively use your hands is also a negative when comparing the two. The dolfin kick is extremely effective underwater but without the use of the arms, the dolfin kick cannot compete with the butterfly done above the water. I hope that answers your question.
There may be a few weird rebuttals but they'd only be weird. Good luck.
