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What’s more important for athletes: training or genetics?

Usain Bolt, Michael Jordan, and Wayne Gretzky are arguably some of the greatest athletes of all time. You watch them on the television breaking record, winning titles or making impossible shots, and you can’t help to wonder, how are they that good? Do they use some secret training method, maybe even a special diet? Possibly, they are genetically gifted? Sports author David Epstein tackles this debate of training versus genetics in his book, “The Sports Gene”. Yes, athletes need to practice to become good, but some are just going to be naturally better than others. If you are 5’6” inches you are going to have to practice dunking a basketball a lot longer than someone who 6’6”. To see how some athletes are naturally better than others lets look at some talented athletes and see what makes them biomechanical specimens. First, we’ll look at Michael Phelps, an American swimmer who not only has multiple world records but also the most decorated Olympian of all time with 28 Olympic medals.

 

For swimmers, biomechanics have found the ideal body for performance. Body features that have been found helpful for swimming is a long torso and long arms.  The long torso reduces the drag on the swimmer and long arms allow for more powerful strokes. Michael Phelps’, who is 6’4”, has the torso proportions of someone who is 6’8” and the leg proportions of someone who is 5’9”, giving him an extremely high torso-to-leg ratio. Not only is Phelps’ torso long, but he also has a long wingspan, measured at 6’7”. Along with Phelps’ unreal proportions, his feet are another huge advantage when it comes to swimming. His size 14 feet help place more force into the water when he kicks. This is a benefit because 90% of a swimmer’s thrust comes from their feet. His ankles also hyperextend 15-degree when he kicks, creating more force. Biomechanically, Michael Phelps’s is a walking fish.

Modified from Hart Blenkinsop, Michael Phelps: The man who was built to be a swimmer 2014

You might be wondering, what would happen if you took someone who has trained to mastery and put them up against someone who is just perfectly gifted. David Epstein mentions this scenario in his book a battle between training and genetics. In the 2007 world high jump final, there are two jumpers left, Stefan Holm and Donald Thomas. Stefan Holm, has a personal best of 7’10.5”, only 2 inches off the world record. Holm has been training most of his life, since he was a child and even won the previous Olympic High Jump final. He is also 5’10” tall, which is very small for a high jumper. Donald Thomas, has a personal best of 7’8.5”. Thomas, on the other hand, is 6’3” and has been jumping for a little over a year and had started high jumping because of a bet with a friend. The two finish the completion and Thomas won clearing a 7’8.5” bar. Even though Holm’s technique was near perfect, Thomas just had the athletic edge. Being taller, Thomas already had a higher center of gravity meaning he had to travel less distance to get over the bar. Thomas also had much longer legs and Achilles tendon. This allows him to store and transfer much more energy into a jump. Thomas was just made to win.

 

For more information:

Michael Phelps: The man who was built to be a swimmer

Nature or Nurture?

Cause and Management of Stretch Marks

Stretch marks. How are they caused? Can they even be treated?

Stretch marks can happen to anyone, of any age, so these questions are important to many. In short, our skin is made up of both collagen and elastin, two elements that support and shape our skin through their natural elasticity. This elasticity, however, does have its limits. And when that breaking point is reached, the collagen and elastin rupture, leaving behind scars many know well – a stretch mark.

Difference between normal skin tissue and stretch mark tissue
From Ud-Din, McGeorge, and Bayat, Journal of the European Academy of Dermatology and Venereology 2015

Stretch marks are caused when skin expands or shrinks at a more rapid pace than the collagen and elastin can accommodate, resulting typically in raised scars that can appear rather inflamed at first. Over time, however, these stretch marks may fade, nearly matching one’s natural skin tone, and usually fall below the surface of the skin. This results in the feeling of a slight indentation when touching older stretch marks.

Like all scars, stretch marks are permanent. But this does not mean that they cannot be treated. There are many treatments available to diminish the visual effect of a stretch mark; not all of them are effective, and some seem not to work at all.

Collagen’s elasticity is controlled by the body’s  cortisone levels, which are commonly associated with episodes of high stress. Basically, heightened cortisone production may decrease the skin elasticity, suggesting that reducing one’s stress may be the most cost-effective and cheap treatment for stretch marks.

Researchers S. Ud-Din, D. McGeorge, and A. Bayat put these post-stretch mark treatments to the test in their paper, focusing on three topical treatment categories – marketed skin creams and oils, over-the-counter home remedies, and prescription medicines and dermatologist procedures.

These topical treatment methods are mainly marketed at increasing collagen production with both hydrating and anti-inflammatory traits. Ultimately, testing yielded mixed results about the efficacy of these treatments. Since participants both massaged their scars and used a topical treatment, the observed improvements to stretch mark appearance could be tied to either of these. Ultimately, however, the researchers did conclude that the age of the scar plays a role in treatment effectiveness, as younger, newer scars were more responsive to treatments.

Beyond these topical treatment methods tested, there are many other dermatological procedures designed to reduce the appearance of stretch marks, including chemical peels, laser therapy, and microdermabrasion. Chemical peels and microdermabrasion focus on removing layers of skin to expose new, non-scarred tissue underneath the stretch mark. And laser therapies are divided into two categories: those that stimulate collagen production and those that promote melanin production (so that the scar tissue matches the natural skin). While these dermatologist procedures can be more effective than the topically applied treatments, they are often expensive and are not guaranteed to be effective. Additionally, dermatologists often combine several procedures, eliminating this treatment for those with cost constraints.

All in all, there are no sure-fire ways to prevent stretch marks, but certain practices do demonstrate that one can prevent stretch marks or at least lessen their appearance fairly cheaply and effectively without any of the products and procedures detailed above. By maintaining a healthy weight, one may avoid the rapid weight loss or gain commonly associated with stretch marks.

For more information, check out these articles on Healthline and AAD.