Is body shaving necessary to improve swimming speed?

There are now more and more men who pluck or shave their body hair. It would seem that the perception of beauty has changed as years go by. This is possible because they feel more comfortable or simply because the standards of aesthetics have changed. Some might say that shaving gives a more youthful appearance or simply gives a feeling of cleanliness and comfort. In the 21st century, this activity has become increasingly popular as more and more men are doing it. However, body shaving has been practised in sports for many years. The first man to do it was bicycle rider Giovanni Gerbi in the early decades of the 20th century. In swimmers, it is not something new or fashionable, since the arms, legs, torso and sometimes the head have been shaved since the 50s. In 1968, they said there was no valid evidence for shaving and thus improving performance; the US historical swimming coach, James Counsilman, even said that what increased was the swimmer’s sensitivity, being able to feel the water’s pressure and that this improved their coordination.

What happens today?

Today, body shaving is something common in all swimming competitions. Clearly, in the photographs of Olympic swimmers, you can see their bodies free of all body hair in the areas where the water could cause friction. To compete, swimmers shave their arms, legs, torso and sometimes their head. But does this activity have any scientific justification? Does it facilitate swimming? Does it improve their performance and above all the speed that is so necessary for an Olympic sport?

Some publications in the public domain indicate that swimmers shave because there is a greater gliding of the body through the water, because they consider it more practical, for aesthetics or because it is easier to dry their body. But of all this, what’s truly scientifically proven? We are talking about Olympic competitions where the most important thing is to break records, swim faster and be better than an opponent in order to win more medals, and for this science has helped sports evolve. Science seeks, through scientific studies, the best techniques, training and equipment, enabling better performance.

Laws of physics

In swimming, the laws of hydrodynamics govern, because the body glides through the water and therefore has to overcome the water resistance. Several factors intervene in this process: the shape of the body directly touching the water, the body area, the density and the position assumed by the body when gliding. As a whole, the body overcomes resistance by gliding through the water. The laminar friction force of the water against the segments is related to its viscosity and its friction with the body surface. So, if we think about it like this, we could say that hair on the body causes more friction and, when it is removed, there is improved gliding.

Only a few scientific studies have been carried out to prove this. Sharp and Costill conducted a study in 1988 because, at that time, there was no published scientific literature on whether shaving could improve performance. They wondered if this practice was effective for reducing body resistance to gliding in the water. This first study was conducted with four men and two women. What was found is that shaving reduced the physiological cost of exercise, but the study could not prove that it decreased swimming times. It was concluded that there was no certainty that shaving improves times, but there was less costly and that this was possibly due to less friction. It also commented on the possible intervention of increased sensitivity.

In 1989, the same authors published another study that was conducted with nine college swimmers. With this study, it was concluded that shaving possibly reduced resistance and had a better physiological cost. While there is little evidence that shaving reduces friction, the reduction in resistance is said to cause a reduction in stroke energy, when compared with unshaven skin. Woods (2004) mentions in his Master's dissertation that swimmers have subjective sensations when shaving, they feel their body mass decreases, water-resistance decreases, flotation increases and they feel it is easier to swim. It has even been mentioned that hair removal is more of a placebo effect because of the gliding sensation of the skin in water. With all of the above, we cannot say that everything has been studied. So far, there is still a lack of objective evidence to show that shaving causes less friction and that this leads to better performance.

The speed of bodies during swimming depends on water propulsion and resistance, so a swimmer can improve by increasing the propulsion force and reducing the resistance forces. More scientific research has been conducted on the technique, since it improves propulsion as well as resistance, so much so that even swimsuits that reduce friction have also been made. That is why they have looked at body alignment, the manner of the stroke, how to position the arms when they are propelled underwater, as well as the fabrics used for swimsuits and the manufacturing process.

Technique and technology, the real answer

Most research in swimming has focused on swimming techniques. Perhaps you remember Michael Phelps, with his wonderful dolphin kick when entering the water or later when turning at the end of the pool. He spends 12 to 13 metres underwater before emerging for the first stroke. That is what gave him the advantage. It is also about where you place your arms when going underwater on push-off, or how to stroke. It seems that the gain in times has been more due to technical adjustments because changes in the technique reduce the drag resistance force and improve propulsion.

Researchers have also focused on swimsuits. They are interested in the fabric, seams, shape and sizes because suits can produce less resistance. In 2008, wetsuits were manufactured. This increased swimming speed and 43 world records were broken in a single event. Since 2010, full bodysuits are not allowed because it is considered technological doping.

Although there is not enough scientific evidence on shaving, it is still recommended among swimmers and they do it. Because ultimately, at an Olympic competition, you have to look for all possibilities that could influence a better result since preparation to get there has been exhaustive and extensive. Athletes cannot allow a millisecond to get in the way of winning. Wouldn’t you do the same?