https://community.usms.org/swimming/f/general/12280/the-power-of-a-thumbI&#39;ve been a swimmer since the 80s for fitness, open water/triathlons kind of swimming...so mostly I only swim crawl stroke. Recently, I occasionally notice that as I swim I will unconsciously allow my thumb to stick out on my right hand. Then I have toen-USTelligent Community 12https://community.usms.org/thread/196785?ContentTypeID=1Wed, 07 Oct 2015 01:19:05 GMT3187ac58-ba85-4314-b79a-c45cd885e09a:9246bc17-cf76-49ea-b97b-9ef3f57eabb0fatboyThere have been studies done on effect of finger separate vs tightly together vs cupped hand and thumb at 90 degrees or held next to fingers. I believe that is also discussed in landmark books Science of Swimming and Swimming Faster. Here&#39;s some links from a quick google search: <a href="http://coachrickswimming.com/2014/11/22/open-or-closed-fingers-a-review/">coachrickswimming.com/.../</a> <a href="http://www.hindawi.com/journals/bmri/2013/140487/">www.hindawi.com/.../</a> <a href="http://www.jbiomech.com/article/S0021-9290(09)00350-9/references">www.jbiomech.com/.../references</a> <a href="http://coachsci.sdsu.edu/swim/bullets/aas31.htm">coachsci.sdsu.edu/.../aas31.htm</a><div style="clear:both;"></div>https://community.usms.org/thread/196704?ContentTypeID=1Tue, 06 Oct 2015 14:10:52 GMT3187ac58-ba85-4314-b79a-c45cd885e09a:a77728f2-451a-493a-af81-011353cde840Former MemberMy guess would be when you are paying attention to your thumb you are also paying attention to the rest of the pull mechanics and therefore catch more water.<div style="clear:both;"></div>https://community.usms.org/thread/196777?ContentTypeID=1Tue, 06 Oct 2015 10:57:55 GMT3187ac58-ba85-4314-b79a-c45cd885e09a:64685a02-2087-40a6-8285-df999d8e2bf6orca1946Closer is better,but it might be the same surface area to do the pulling.<div style="clear:both;"></div>https://community.usms.org/thread/196765?ContentTypeID=1Tue, 06 Oct 2015 09:00:19 GMT3187ac58-ba85-4314-b79a-c45cd885e09a:1fa5ef38-a35c-4855-a1e1-4ccdb28345f7Bill SiveMolehill<div style="clear:both;"></div>https://community.usms.org/thread/196685?ContentTypeID=1Mon, 05 Oct 2015 08:21:14 GMT3187ac58-ba85-4314-b79a-c45cd885e09a:9a0db0cd-61b0-43b3-9b05-36c71b6457ba__steve__If it helps, Roland Schoeman&#39;s right thumb points perpendicular to the hand surface.<div style="clear:both;"></div>