Get a handyman! Blue-collar jobs that involve heavy lifting increase sperm count and testosterone levels in men by up to 50%, Harvard study finds
According to a study, blue-collar jobs that involve heavy lifting actually make men more masculine.
Those with physically demanding jobs had 46 percent higher sperm concentration and 44 percent higher total sperm count than employees.
They also had higher levels of testosterone — the sex hormone that gives men large testicles and aids in sperm production.
Lifting heavy objects — and exercise in general — has been shown to reduce inflammation in the body, which is linked to better sexual health.
Sperm counts in men have more than halved since the 1970s, attributed to lack of exercise and poor diet.
The researchers didn’t speculate as to why the correlation might have occurred, but previous studies suggest that exercise, such as heavy lifting, promotes healthy levels of hormones that create a better environment in the testicles for sperm production
Men who said they lifted often had almost double the sperm concentration of those who said they never did heavy lifting at work
The study, published in Human Reproduction, looked at 377 men in couples seeking treatment at a fertility center.
The men – who had an average age of 36 and were mostly white – completed a questionnaire about lifting or moving heavy objects, their typical shift and physical exertion at work.
Samples of her semen were analyzed to see the levels of various reproductive hormones.
Of the men who completed the survey, 12 percent said they often lift or move heavy objects at work. These men had 46 percent higher sperm concentration and 44 percent higher total sperm count compared to men who reported never moving heavy objects at work.
Sperm concentration is the number of sperm per unit volume (milliliter) of semen and total sperm count is the total number of sperm in the ejaculate.
The researchers didn’t speculate as to why the correlation might have occurred, but previous studies suggest that exercise, such as heavy lifting, promotes healthy levels of hormones that create a better environment in the testicles for sperm production.
Experts have said that even moderate exercise curbs oxidative stress, which damages sperm.
It was found that the men who engaged in heavy or moderate exertion also had higher concentrations of testosterone compared to those engaged in light exertion.
Those who worked evening or rotating shifts had 24 percent higher testosterone levels than men who worked day shifts.
Men, who often did a lot of physical labor at work, also had higher levels of estrogen, the female sex hormone.
Researchers hypothesized that this is because excess testosterone is converted to estrogen by the body to maintain a balance of the two.
Because the participants were men from couples seeking fertility treatment, the results may not apply to men in the general population.
However, other studies have confirmed that men with a sedentary lifestyle do worse off on several semen parameters, including volume, viability, and motility.
Other research published in the journal Human Reproduction Update showed the declining sperm rates in men.
It included data from 57,000 men from 53 countries – the largest study ever conducted.
The paper showed that sperm count — or the amount of sperm in an ejaculation — fell from 101 million to 49 million sperm per millimeter of semen between 1973 and 2018.