Men who want children in the future should start exercising now, a new study suggests.
A study conducted on mice showed that males who exercised before conception had kids with healthier metabolisms, including lower levels of body fat and better processing of glucose in the blood.
This was the case even if the father ate a mostly high-fat diet.
Past studies have linked a paternal diet to metabolic changes in offspring and the development of type 2 diabetes.
The team from Ohio State University Wexner Medical Center says its findings suggest exercise could negate the effects of a poor diet by changing key genes in the father’s sperm.
Researchers say fathers who exercise before conception have kids with healthier metabolisms, even if the father ate a mostly high-fat diet (file image)
For the study, the team fed one group of male mice a normal diet and the other group a high-fat diet.
Researchers kept some mice from each group sedentary while the rest were allowed to exercise freely.
After a three-week period, the male mice mated and their offspring ate a normal diet – but were kept sedentary – for one year.
The adult offspring from mice that ate a high-fat diet and didn’t exercise were more likely to have higher levels of body fat and problems processing glucose in the blood.
But the offspring of mice who exercised, regardless of what type of diet they ate, weighed less, had less body fat, and had an improved glucose metabolism.
‘Here’s what’s really interesting; offspring from the dads fed a high-fat diet fared worse, so they were more glucose intolerant. But exercise negated that effect,’ said Dr Kristin Stanford, an assistant professor at The Ohio State University College of Medicine.
‘When the dad exercised, even on a high-fat diet, we saw improved metabolic health in their adult offspring.’
By examining the fathers’ sperm cells, the researchers found that lack of exercise was associated with decreased sperm motility and multiple changes to sperm small RNA, which carries instructions from DNA to parts of the body that make proteins.
The results were similar to previous studies which found that when female mice exercise, their offspring have healthier metabolisms.
‘Based on both studies, we’re now determining if both parents exercising has even greater effects to improve metabolism and overall health of offspring. If translated to humans, this would be hugely important for the health of the next generation,’ said Dr K Craig Kent, dean of the Ohio State College of Medicine.
The team says that despite its findings coming from mice, there is potential that this translates to humans.
‘We know that in adult men obesity impairs testosterone levels, sperm number and motility, and it decreases the number of live births,’ Dr Stanford said.
‘If we ask someone who’s getting ready to have a child to exercise moderately, even for a month before conception, that could have a strong effect on the health of their sperm and the long-term metabolic health of their children.’
Studies over the past decade in the field of epigenetics – the study of inheritable traits that are carried outside the genome – have provided support to the idea that the environmental conditions experienced by a parent can affect disease risk and other features of future generations.
Many studies have suggested that fathers with poor diets raise the risk of terrible health effects on their children, but this is among the first to suggest the contrary.
A study earlier this month conducted on mice from Florida State University found that fathers exposed to nicotine raised the risk of their children and even their grandchildren developing ADHD.
Another February 2017 study conducted on mice by the University of Massachusetts Medical School found that the offspring of nicotine-exposed fathers were protected from toxic levels of nicotine compared to the offspring of fathers that were never exposed.
But there was a caveat: these children were also born with an inherited tolerance to drugs, meaning they could be unresponsive to certain antibiotics or even chemotherapy.