Grab The 20's

Men In This Line Of Work Tend To Have A Higher Sperm Count

A new study has found that male fertility can be boosted by picking up some dumbbells.

Workers are helping to load goods into containers.
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We already know that lifting heavy weights is a great way to increase longevity, but a new study has found that lifting may also provide a boost to male fertility.

Up to 40% of infertility cases can be attributed to male-related factors such as poor sperm count and semen quality, which are boming more prevalent. Previous research has found that between 2000 and 2017, sperm count and quality in men seeking fertility treatment decreased by 42%. Male infertility has also been connected to certain chronic conditions such as heart disease and autoimmune disorders.

To examine factors contributing to male fertility, researchers from Brigham and Women’s Hospital, a Harvard Medical School teaching hospital, examined data and samples collected from the Environment and Reproductive Health (EARTH) cohort, organized to examine how lifestyle and environment affect reproductive health.

“We already know that exercise is associated with multiple health benefits in humans, including those observed on reproductive health, but few studies have looked at how occupational factors can contribute to these benefits,” study author Lidia Mínguez-Alarcón, a reproductive epidemiologist in Brigham’s Channing Division of Network Medicine, said in a statement. “What these new findings suggest is that physical activity during work may also be associated with significant improvement in men’s reproductive potential.”

Of the 1,500 total samples, researchers examined data from a portion that included 377 samples from men in couples seeking fertility treatment. They found that men who reported lifting heavy objects as part of their job had a 44% higher total sperm count and a 46% higher sperm concentration than men who didn’t lift things as part of their jobs.

Men who performed physical labor also had higher levels of testosterone and estrogen than those who did not. “Contrary to what some people remember from biology class, ‘male’ and ‘female’ hormones are found in both sexes, but in different amounts,” said Mínguez-Alarcón. “In this case, we hypothesize that excess testosterone is being converted into estrogen, which is a known way for the body to keep normal levels of both hormones.”

Although the research has far-reaching implications, there are no guidelines for the amount of weight or repetition necessary to bolster sperm count, and the study does not prove causality that lifting improves sperm count. Additionally, the study only looked into lifting as part of a man’s job, not for exercise in and of itself. Further research is also necessary to determine if the correlation between physical labor and sperm count holds true for men who are not seeking fertility treatment.

“Reproductive health is important in its own right, but more and more evidence suggests that male infertility can give us insight into broader public health issues, including the most common chronic diseases,” said Mínguez-Alarcón. “Uncovering actionable steps people can take to improve their fertility stands to benefit all of us, not just couples trying to conceive.”