Humans are arguably near the limits of elite performance in some sports, where records are either marginally improved, or stagnant for years.
But Dr Inigo Mujika believes there is still potential for top athletes to make significant headway in swimming.
He said: "Swimming is a sport where there is still room for improvement because it is not land-based and we are land animals.
"So the fact that we need to adapt to the water environment makes it more possible to keep improving and keep adapting."
The Spaniard would know better - he has PhDs in the biology of muscular exercise and physical activity and sport sciences, and is a high-level swimming and triathlon coach.
Dr Mujika also served as a physiologist for the Spanish swim team between 2009 and 2012, helping the likes of double Olympic silver medallist Mireia Belmonte prepare for London 2012.
The lanky academic is in town as the keynote speaker for the third annual Singapore Sports Institute (SSI) Annual Symposium, which started yesterday and ends today.
During his 80-minute keynote speech, he spoke, among other things, about his personal experience with the Spanish swim team.
He regularly followed Belmonte on training runs and carted bottles of water back to the team hotel from the supermarket to ensure that his athletes were properly hydrated.
While he was embedded with the swim team for years, local national sports associations usually do not have that luxury, often sharing the SSI's resources and personnel in their own training and preparation.
But he cautioned during his speech to some 250 participants that sports science is useful only when the appropriate blend of information is correctly used by the coach, whom he likened to a chef.
He said: "I think it's still possible for a coach to succeed at the highest level without using sports science.
"There are examples of these coaches and some have even failed when they eventually get access to sports science.
"So I am not saying that sports science is the solution to all the problems but, in some instances, they can make a difference.
"And what is clear is that in sports where there have very developed sports-science programmes, it's going to get more and more difficult to succeed without them."
The United States' elite swimming programme is arguably the strongest in the world, he added, and it would be hard for other nations, even with China making inroads in Olympic swimming in 2012, to top the Americans' training structure.
This article was first published on Nov 11, 2014.
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