Hair and jewelry mean more weight to move when your racing. When we’re looking at hundredths of second couldn’t a few extra grams (or even fractions of a gram) mean the difference between winning and losing?
I’m assuming you’re talking about sprinting? If the weight your body is carrying made a difference in sprinting, then Olympic running would be selecting for smaller, i.e. short, people, the way women’s gymnastics selects for short girls. And since Olympic sprinters don’t tend to be short overall the way female gymnasts tend to be short overall, I thus infer that within certain parameters (obviously obese people aren’t going to be Olympic runners), it doesn’t make that much difference how much a runner weighs, physics-wise, and that jewelry and long hair don’t signify. It’s all about muscle twitch fibers, and coordination, and training.
Ok, so are you saying that if a sprinter wore a backpack full of lead they’d be fine? Body weight (muscle) and things you carry that don’t add any benefit at all are quite different.
And they should run naked too!
Really, I don’t think a gram or two matters, considering a 165 lb person weighs 75,000 grams. Reaction time is a much greater factor.
People used claim that any body hair increased water resistance for swimmers, so they should shave it all off.
About a third of a century ago, Mark Spitz with his mustache showed that this wasn’t true. Or at least, that the difference was minor enough to be easily overcome by better swimming performance.
I imagine it’s the same with sprinters: a few grams of jewelry don’t matter in comparison to the total body weight.
Resistance due to drag is much less in air compared to in water because of the viscosity difference, enough so that it’s less than negligible.
Although a slightly different situation, heavier motorcycles don’t necessarily accelerate or brake less quickly because they have more inertia; it also gives them more normal force (which gives more traction).
Did you watch any of the US Men’s swimmers during the current Olympics? Other than what’s on their head, from the waist up (and a bit lower, too!) they are all shaved.
I said “within certain parameters”. Which would include “not being facetious”. 
And I said, “…and that jewelry and long hair don’t signify”, so we’re talking about jewelry and hair here, not obese people or lead backpacks.
Peak athletic performance is also about feeling good. If two tiny earrings or a necklace make an athlete feel better about themselves it will translate into better times. They can be good luck charms, or reminders, or just something to make them more comfortable on camera after the race. The minuscule weight penalty is a minor consideration.
Attitude is part of the whole package.
oddly most sprinters are short. the one fellow that is over 6’ is quite different, and has been remarked on repeatedly in the last few days. there is a striking difference in his gait compared to the other sprinters.
Obviously, you’ve never been a competitive swimmer. A mustache won’t slow you down nearly as much as having hair on your chest, legs, etc.
Are we being whooshed with this answer? People used to claim this? They shave now!
Empirical evidence for this?
Don’t know if there have been any studies, but isn’t it a bit obvious? A mustache is a few square inches, whereas chest+ legs are square feet. Depending on the stroke, a mustache might not be in the water the whole time. Do you have any reason to believe that a mustache would slow one down more than body hair?
I’m asking for empirical quantification of the supposed drag effect of body hair, whether on the face, chest, or legs.
The simplest answer is the correct one: It just doesn’t matter, certainly not anywhere near 0.01 seconds of time. Similarly, an athlete doesn’t try to shave a gram or two off his/her weight by skipping that last pea in the previous night’s meal.
I was wondering about jewelry too. Seems like it could snag your hair and distract you, if nothing else. That one sprinter raced with his necklace in his mouth, not sure what that was all about.
Ah, well, the way I read your previous post I thought you were asking about the difference between mustaches and chest hair. I can only tell you that I dropped a second off my fifty time after shaving when I was on the swim team in HS. It was also a faster pool, I tapered (easier workouts the week before), and it was the big meet, so who knows how much the shaving helped. But you definetly feel faster. I’m sure someone’s done a study, as even bicyclists have been known to shave their legs.
Cyclists have an additional motivation to shave their legs - skid grazes are much easier to clean up and heal faster if they are not full of body hair.
Funny story from my uni days: a girl I went to school with was in the same same halls of residence, and her boyfriend (a competitive cyclist) was coming to visit. I was asked what he was like. I didn’t know him at all, but I was able to reply truthfully
I don’t wish to cast aspersions on his character, but I do know that he shaves his legs.
I got thumped for that, but it was worth it.
Si
Shaving absolutely helps with swimming performance, and probably helps slightly for longer distance runs.
Sprints aren’t affected by such small factors. Reaction time, race strategy, running technique, and overall conditioning easily outweigh jewelry weight or drag from hair. I personally wouldn’t want a necklace smacking me in the face, but some people don’t seem to mind. The necklace in the mouth thing is a bit odd, but considering that for sprints up to around 200 m some of the sprinters don’t even bother to breathe during the race, saving their effort for running instead, it’s not all that weird.
More studies about swimming performance:
http://coachsci.sdsu.edu/swimming/hydro/table.htm