The world of exercise and fitness is packed with hundreds of scientific “facts”. I use the term “facts” advisedly as the difference between real science and proven science can be substantial. Also, scientific knowledge changes as we learn more about the detail of how things work. And many “experts” say things that sound right but really have little basis in fact. What does this mean for those trying to get fitter, stronger and healthier?
We are fortunate to live in an age where we know more about our world at the macro and micro levels than ever before. Discoveries by archaeologists, improvements in microscopy, research by chemists and physicists, the age of genetics – all of these mean we know about ourselves and the world than ever before.
But all that data needs to be tempered by a simple test – can you trust the research?
For example, in the early 1990s, researchers claimed to have found a way to use cold fusion to safely generate energy. But, after much fanfare the claim was debunked. Thats not to say the science is totally without merit in being investigated but that we need to be cautious before simply accepting something just because of a published article and some attention.
Back in 1980s I volunteered at a sea turtle research facility at Mon Repos in Queensland. One of the things I learned then was that sea turtles have a very long lifespan – probably in excess of 100 years and maybe as long as 200 years. Some species of sea turtle might not reach sexual maturity until they are in the 60s. The trouble is, because of their lifespan, at the time we weren’t really sure as the lifespan exceeded our efforts to tag and carry out longitudinal studies.
However, many cultures used sea turtle eggs as a food source. When this was limited to indigenous populations it was OK. Indigenous races were able to eat enough without compromising entire laying seasons. However, modern urbanised populations saw turtle eggs as a delicacy and a profitable market for them developed.
There was little understanding of the impact this could cause because there was an understanding that sea turtles had a much shorter lifespan. This was based on knowledge that had changed through research but was either not known or ignored because “sea turtles have a 20-year lifespan” had been published at some point and therefore must be right.
How do muscles get bigger?
Lots of people engage in weight-bearing or resistance-based exercise in order to increase muscle mass. But here’s a question – do muscles get bigger by adding more fibres or by retaining the same number of fibres but making them bigger?
There are two terms to be aware of – hypertrophy and hyperplasia. Hypertrophy refers to an increase in the size of muscle fibres. Hyperplasia refers to an increase in the number of fibres.
At various times in the past, one of these was believed to be “truth”.
A scan of some literature tends to suggest hypertrophy is the main reason muscles get bigger with resistance training although there is research suggesting hyperplasia does occur (do your own research and draw your own conclusions – I’m not interested in inciting an argument here).
It’s fair to say that the paleo diet is one of the biggest trends in health and well-being. It’s based on the principle that our bodies evolved to eat a diet based on “natural” foods and a foraging culture.
And, if you read the books and listen to fans of the diet all of this sounds very reasonable. But what if “sounds reasonable” and “scientific method” don’t correlate? It doesn’t make the paleo diet any less viable as a way of managing weight and feeling good. But it may mean you need to reconsider the reasons it’s a good diet.
The article The Paleo Diet Is Not Based On Science by human evolution specialist from UNSW Australia Darren Curnoe debunks some of the scientific claims made about the paleo diet. It’s worth noting that he doesn’t say paleo is bad – but he notes that the reasonable sounding assumptions about it are probably flawed.
What’s the Lesson?
My advice is very simple – if you’re making a change to your diet or training regime based on some scientific knowledge or understanding you need to do your research.
If we are to accept Curnoe’s suppositions, then the science behind paleo diets comes from a single piece of research by by Eaton and Konner published in the New England Journal of Medicine in 1985 (here’s the article).
There’s an old saying – “one swallow does not a summer make”. In other words, one published article, even if it’s peer reviewed, is probably not enough to make a leap to something being 100% reliable.
Despite what we might think, science is not always absolute. We continue to learn more and more about our world every day and that means old assumptions and “facts” are called into question and sometimes debunked.
I’m not saying paleo or a specific training system that promotes hyperplasia over hypertrophy is right or wrong. Only you can make the judgement of what gives you the benefits you are looking for. But if you’re basing those judgements on science, retain your objectivity and be prepared to be challenged as science learns more and questions those judgements.