Moderate intensity exercise done three to four times a day can help men produce 'healthy swimmers', according to new research.

Australian men who spend countless hours on the couch watching the cricket over summer could be jeopardising their fertility.

A new study, published in the journal Reproduction, has found exercising between three to four times a week can improve a man's sperm count.

In fact, German and Iranian researchers found that moderate yet "continuous" and regular exercise improved a man's sperm quality more than those men following popular intensive, high interval exercise programs.

"Our results show that doing exercise can be a simple, cheap and effective strategy for improving sperm quality in sedentary men, said lead author Behzad Hajizadeh Maleki.

The study looked at 261 men who did not follow a regular exercise program.

They were divided up into groups and asked to follow different exercise programs that included running on a treadmill for 30 minutes or quick bursts of sprinting three to four days a week.

Semen samples were taken and analysed before, during and after the different exercise regimens.

The men who participated in the moderate intensity continuous training (MICT) program showed the biggest improvements in sperm quality, and also maintained these benefits for longer compared to men who did the high intensity interval training (HIIT).

Compared to the control group, those following the MICT training had:

• 8.3 per cent more semen volume
• 12.4 per cent higher sperm motility
• 17.1 per cent improved sperm cell shape/morphology
• 14.1 per cent more concentrated sperm
• 21.8 per cent more sperm cells on average

It's important to note, however, that male infertility is a complex problem and isn't just based on sperm count, said Mr Maleki.

Infertility affects about one-in-six Australian couples of a reproductive age and experts advocate healthy diet and exercise as important lifestyle factors men and women can take to help their chances of getting pregnant.

Reducing alcohol consumption, quitting smoking and losing excess weight are also recommended.