As marathon season approaches, thousands lace up their trainers and hit the pavement with a goal in mind: stamina, strength, and the finish line. But If you’re thinking about starting a family — either now or in the near future — it’s worth considering another finish line: your fertility health.
Fitness and male fertility are more closely connected than many people realise. Your training habits, nutrition choices, and recovery routines can directly impact your sperm health — and ultimately your chances of starting a family.
First, a Quick Primer on Egg and Sperm Quality
Egg quality refers to an egg’s ability to be fertilised and develop into a healthy embryo. It naturally declines with age, especially after 35. If you’re curious about what influences egg health and how to support it, OVUM offers brilliant science-backed resources focused on female fertility.
Sperm quality is defined by:
- Volume (amount of semen)
- Concentration (sperm count)
- Motility (how well sperm swim)
These three factors determine Total Motile Sperm Count (TMSC) — a strong predictor of male fertility potential and the key metric used by ExSeed’s at-home sperm test.
While moderate exercise is well-known to boost sperm health, prolonged high-intensity training — like preparing for a marathon — can have the opposite effect if you’re not careful.
What the Research Shows
A 2017 study in Reproduction found that moderate aerobic exercise improved sperm count, motility, and shape in men who exercised 3–5 times per week.
However, excessive endurance training — especially without proper recovery or nutrition — is associated with:
- Lower testosterone levels
- Increased cortisol (the stress hormone)
- Disrupted hormone balance
- Reduced sperm concentration and motility
Cyclists and long-distance runners are particularly affected when training exceeds 90 minutes per day, especially if paired with low body fat or caloric deficits.
Fertility-Friendly Training Plans for Men
If you’re trying to conceive, it’s possible to stay fit and fertile — you just need a more intentional approach to your workouts.
Try this science-backed framework:
- Frequency: 3–5 workouts per week
- Intensity: Moderate (60–75% of your max heart rate)
- Duration: Ideally under 90 minutes per session
- Type:
- Cross-training (swimming, resistance training)
- Interval runs vs. constant long-distance
- Rest days built into your plan
Remember: more isn’t always better. Recovery is when your body builds strength and balances hormones — both vital to sperm production.
Nutrition for Endurance and Fertility
Fueling a running body is different from fueling a fertile body — but the two don’t have to compete.
What Sperm Need to Thrive:
- Zinc: Supports testosterone and sperm production (found in pumpkin seeds, beef, lentils)
- Omega-3 fatty acids: Improve sperm motility and reduce inflammation (found in oily fish, walnuts, flaxseed)
- Vitamin C and E: Protect sperm from oxidative stress (citrus, spinach, almonds)
- Coenzyme Q10: Linked to improved sperm morphology
Try to limit ultra-processed energy bars or sugary drinks — regular consumption may affect long-term health and hormonal balance.
For women, focus on iron-rich foods, healthy fats, and complex carbs to support hormone balance and ovulation — especially with increased physical activity. For a deeper dive into how nutrition impacts egg health, OVUM has created a powerful evidence-based guide.
Weight, Body Fat & Fertility
While marathon training often leads to weight loss, very low body fat in men can disrupt hormone levels, lowering testosterone and reducing sperm production.
A 2020 meta-analysis in Andrology showed that men with obesity were 42% more likely to have low sperm counts — but extreme leanness can also suppress reproductive hormones.
Aim for a healthy, sustainable body composition, not a race-weight mentality, if fertility is part of the plan.
Don’t Underrate Sleep & Recovery
You may track every mile — but do you track your sleep?
Sleep deprivation:
- Reduces testosterone
- Impairs recovery
- Worsens sperm quality
A studyfound that young men who slept only 5 hours per night for one week experienced a 10% to 15% reduction in daytime testosterone levels compared to when they had a full night’s sleep.
Try this:
- Get 7–9 hours of sleep
- Avoid blue light before bed
- Refuel with carbs + protein after training
- Don’t skip rest days — your fertility depends on them too
Take Control of Male Fertility
The good news: sperm regenerate every 72 days. That means the positive changes you make now — in your workouts, diet, or sleep routine — can start making a difference in just a few months.
ExSeed’s at-home sperm test allows you to track your Total Motile Sperm Count easily and privately — giving you control and insight into your fertility during training season and beyond.
Final Thoughts: Finding Balance in the Race for Parenthood
Training for a marathon is a powerful, motivating goal — and so is building a family. These two ambitions don’t need to be at odds.
By staying mindful of how fitness affects fertility, you can strike a balance between chasing personal bests and giving your future family the best chance possible.
Fertility is a team effort. While ExSeed supports men on their journey to fatherhood, OVUM offers the same empowering insights for women — from ovulation science to egg health and fertility nutrition.
So run your race. But keep fertility in stride, too.
This article is for general informational purposes only and is not a substitute for professional medical advice. If you have concerns about fertility or health, please speak to a healthcare professional.
