Running in Your 50s: 7 Ways a Man's Body Changes (and What to Do About It)
Updated: 12 hours ago
Written by Andy Hood · Ultra runner, cancer survivor and Runna ambassador
Updated 6 November 2026 | Originally published July 2026
Article contains affiliate links/codes which support this blog and the cancer charity work Andy undertakes
The short answer: Running in your 50s gets harder because men lose testosterone, muscle, bone density and aerobic capacity (VO2 max), and need about 72 hours between hard sessions instead of 48. But trained men lose aerobic fitness at roughly half the rate of untrained men, and twice-weekly strength training slows muscle and bone loss. Much of what feels like ageing is detraining.
Tired legs, tight Achilles, and an increasingly urgent relationship with hedgerows. If you're a bloke in your 50s who still laces up, this one is for you.
Key takeaways
The changes are real. Testosterone, muscle, bone and aerobic capacity all measurably decline from around 50.
The rate of decline is largely up to you. Trained men lose aerobic capacity at half the rate of untrained men, and strength training is the most effective way to slow muscle loss.
Persistent symptoms belong with a GP. I'm a runner, not a doctor: take ongoing fatigue, bowel changes or anything that worries you to your GP.
Running in Your 50s: How a Man's Body Changes at a Glance
What changes after 50 | Roughly how much | What actually helps |
Testosterone | Total falls ~1.6% a year, free testosterone ~2 to 3% | Eat enough, sleep, limit hard sessions, see a GP if symptoms persist |
Muscle mass and strength | Mass down 1 to 2% a year, strength down 1.5 to 3% | Resistance training, 2 to 3 sessions of 30 minutes a week |
Gut and bowels | Affects 30 to 90% of distance runners | Low fibre pre-run, practise fuelling, loose kit, hydrate |
Recovery and tendons | Hard sessions need 72 hours, not 48 | Warm up and cool down every run, build mileage 5 to 8% a week |
VO2 max | Down ~10% per decade untrained, ~5% if trained | Keep some intensity, build Zone 2 volume, stay consistent |
Bone density | About 1 in 5 men over 50 will have an osteoporosis-related fracture | Lifting and impact work, calcium and vitamin D, less alcohol |
Fat distribution | Metabolism is stable from 20 to 60; fat shifts to the waist | Lift, eat 1.0 to 1.2g protein per kg a day, sleep |
Contents
My Experience: Running in My 50s After Cancer
I'm a runner in my early 50s with around 25 years of running behind me, and I've noticed real changes in my body. Cancer in 2021 and chemotherapy have likely magnified some of them, but I'm pretty sure they don't account for all of them.
Tiredness is a big factor. I sleep more. I feel I need to rest more. My days of fast pace seem to slip away into a distant past that even Professor Brian Cox couldn't locate. I have earlier nights and later mornings, although I do still get up at 4:30am for a speed interval session, as I did this morning. Those early starts are just less frequent, and often less early.
Then there are the Achilles, which every morning feel like they have run 100 miles in the night.
They are tight and take a few minutes to warm up. Coming down the stairs, avoiding three cats under my feet, takes a little more thought and reassurance from the bannister.
And if we are going to get really personal, finding a tree or bush mid-run has definitely become a thing. We are not just talking about a quick pee behind the bush. My bowels are not as rock solid as they once were.
Strength training has featured in my running programme for the past few years. I knew my body was not as flexible as it was even in my 40s, and I was more prone to injury.
So it got me thinking. I can't be the only runner in his 50s dealing with this, and as I'm incredibly open about the challenges I go through, a blog article seemed a good bet. You may find it reassuring and useful.
With a little research I came up with the top six, maybe seven (I am at an age where I change my mind often), areas where men's bodies change as we age. More importantly, I looked at whether we just have to accept them or whether there are positive actions we can take.
Spoiler: it's mostly the second one. And it ended up being seven. I did warn you about the changing my mind thing.
1. Low Testosterone in Men Over 50: Symptoms and the Effect of Running
It's the hormone everyone has heard of and almost nobody talks about at parkrun.
Why it happens: Total testosterone falls by about 1.6% a year from middle age, a little faster after 50 (Massachusetts Male Aging Study). It's a slow slide, and the symptoms (low energy, less strength, lower libido, flat mood) look exactly like "getting older", so most men never spot it. Very high mileage on too little food can push it lower still.
The good news: in a trial of men aged 50 to 70, exercise did more for fitness and strength than testosterone treatment. The thing you're already doing beats the thing being sold to you on Instagram.
What to do:
Eat enough to fuel your training, especially on big mileage weeks
Protect your sleep
Keep truly hard sessions to two a week at most
If symptoms persist, ask your GP for a blood test rather than self-diagnosing from a forum
2. Muscle Loss (Sarcopenia) After 50: Why Runners Need Strength Training
This is the single biggest reason I'd tell any runner over 45 to get into a gym.
Why it happens: Muscle mass peaks in your 30s, then falls by 1 to 2% a year, and strength drops even faster. The loss speeds up after 50. Here's the bit that caught me out: running doesn't fix it. Running is brilliant for your heart and your head, but only resistance training reliably holds on to muscle, which is why international guidelines recommend it first.
What to do:
Do two 30-minute strength sessions a week, on easy or rest days
Stick to compound moves: squats, lunges, deadlifts, step-ups and calf raises
Add a little weight or a few reps every couple of weeks
Start this week, not next January
My own week is one coached gym session, one plyometric session and daily banded ankle work. The full routine is in my guide to strength training for runners.
3. Runner's Diarrhoea (Runner's Trots) After 50: Causes and Prevention
Right. Deep breath. Nobody writes about this properly, and it leaves people thinking they're the only one. You're not.
Why it happens: Between 30 and 90% of distance runners get gut symptoms. When you run hard, blood is diverted from your gut to your legs, and the jostling, pre-race nerves and whatever you ate all add to it. It's a running issue more than an age one, but in your 50s it tends to stack on top of other digestive changes. For me, cancer treatment hasn't helped either.
What to do (based on Mayo Clinic advice):
Cut high-fibre and gassy foods the day before a long run or race
Go easy on caffeine and fatty food in the 3 to 6 hours beforehand
Skip ibuprofen and other anti-inflammatories before a big effort
Wear kit that's loose around the waist, and stay hydrated
Practise race-day food and gels in training, and never try anything new on the day
And this matters: a change in bowel habit that sticks around, or any blood, is not runner's trots. See your GP. I found my cancer because I acted on something that had changed. Do the same.
4. Slower Recovery, Achilles Stiffness and Injury Risk After 50
This is the one I feel most, every morning on the stairs, dodging three cats.
Why it happens: Muscles repair more slowly and tendons lose some of their stretch with age. So hard sessions need about 72 hours between them instead of 48, and the Achilles takes longer to wake up. The good news: recreational running does not wreck your knees. Recreational runners actually have lower rates of hip and knee arthritis than people who don't run.
What to do:
Warm up and cool down every run, no exceptions. If you take one habit from this article, make it this one
Leave 72 hours between hard sessions
Build weekly mileage by 5 to 8%, not the old 10% rule
Treat sleep as part of your training
See a physio if Achilles stiffness lasts, gets worse or hurts during runs
When you choose a running training plan, pick one that matches where your body is now and builds from there.
5. VO2 Max Decline by Age: Why Running Feels Harder After 50
If you've finished a steady run thinking "that should not have been that hard", this is why.
Why it happens: VO2 max is how much oxygen your body can use at full effort. It falls about 10% per decade after 30 in men who don't train, mostly because your maximum heart rate drops by roughly a beat a year. Men who keep training lose only about half that, so much of what we blame on ageing is really lost fitness.
Age | Average man (ml/kg/min) | Top 10% of men (ml/kg/min) |
40s | 35 | 51 |
50s | 29 | 43 |
60s | 25 | 37 |
These figures come from the FRIEND fitness registry, which tested men in US labs rather than runners, so the average column includes plenty of sedentary men. Runners should compare themselves with the right-hand column. Men with years of endurance training typically test around 45 to 55 in their 50s and early 60s, which puts them level with average men 20 to 30 years younger.
What to do:
Keep one session a week with some intensity: intervals, tempo or hills
Make most of your other running easy, Zone 2 miles
Stay consistent through winter, busy work spells and the weeks you can't be bothered. Consistency is the intervention
My own VO2 Max is currently 52, it dropped to around 48 after the surgery this year and though a carefully managed Runna training programme it has gradually increased.
6. Bone Density and Osteoporosis in Men: Does Running Help?
I nearly left this one out, which is exactly why it's here.
Why it happens: About 1 in 5 men over 50 will break a bone because of osteoporosis, and it often goes unnoticed until something breaks. Falling testosterone plays a part. Running helps because it's weight-bearing, but the impact is lower than lifting or jumping, and high mileage on too little food can actually weaken bone.
What to do:
Lift weights twice a week (the sessions from section 2 count)
Add 10 minutes of jumping a week: hill sprints, skipping or plyometrics
Get enough calcium and vitamin D, and eat enough overall
Go easy on alcohol, and don't smoke
If you've had a fracture or have low testosterone, ask your GP about a bone density scan
If you are looking for strength training videos I recommend checking out RunLab on YouTube. Chris & Vlad produce excellent content which I follow throughput my training blocks.
7. Metabolism and Belly Fat in Men Over 50
My fat has moved to my waist, and running alone doesn't shift it. And before you ask, I don't drink and I don't eat much sugar.
Why it happens: It's not your metabolism. A large 2021 study found metabolic rate holds steady from age 20 to 60. The real culprits are lost muscle, which lowers the calories you burn at rest, and falling testosterone, which nudges fat towards your middle. On top of that, your body claws back roughly a quarter of the energy you burn exercising, so more miles rarely shrink a waistline on their own.
What to do:
Lift. It protects the muscle that keeps your resting burn up
Eat more protein, spread across the day. Aim for about 1.0 to 1.2g per kg of body weight (80 to 96g for an 80kg man), roughly 25g at each meal. Most runners are fine at dinner and hopeless at breakfast
Sleep properly. One night without sleep can cut testosterone by almost a quarter
Measure your waist, not just your weight. If it keeps growing, talk to your GP
For a nutrition plan built around you, see a registered dietitian rather than a running blog, mine included.
Can You Slow Ageing as a Runner? What the Evidence Shows
Yes. In all seven areas, how fast your body declines depends heavily on what you do, even though some change is unavoidable. Here's where I landed after all the reading.
There are things to accept.
My fastest times are behind me. My recovery is slower and always will be. My Achilles will need their morning warm-up ritual for the rest of my running life.
Fighting those facts is a fast route to injury and frustration, and I've watched too many runners in their 50s break themselves trying to be 35 again.
But look at the pattern across all seven areas:
Testosterone: exercise beat testosterone treatment in a randomised trial of men aged 50 to 70
Muscle: strength training is the most effective proven intervention against sarcopenia
Gut: mostly manageable through fuelling strategy and practice
Recovery and joints: recreational runners have no more arthritis than non-runners, and recovery habits are within your control
Aerobic engine: trained men decline at half the rate of untrained men
Bone: resistance and impact work plus proper fuelling directly protect bone
Fat distribution: your metabolism hasn't slowed, so muscle, protein and sleep are the levers that work
Seven for seven. That's not a coincidence, it's the whole point.
The way I look at it now: I've got less to work with, so I'm going to be smarter with what I've got. Assess it, reframe it, adjust it. That mindset got me back to running after cancer and again after emergency surgery this year, and it works just as well for the slow creep of the birthday count.
8 Training Tips for Runners Over 50
The eight habits below cover every change in this article. If I were starting today, this is exactly what I'd do.
Do two strength sessions a week. Not "when I have time". In the plan, with a name and a slot.
Add something that jumps. Plyometrics, hill sprints, skipping. Ten minutes a week does more for your bones than another easy 5K.
Treat sleep as training. It's where the adaptation happens, and we need more of it than we used to.
Eat enough, and get enough protein. Under-fuelling in your 50s hits hormones, muscle and bone all at once. This is not the decade for training on fumes.
Leave 72 hours between hard sessions, not 48. Build mileage by 5 to 8% a week.
Practise race-day fuelling in training. Every gel, every drink, every pre-run breakfast. Your gut needs rehearsals.
Warm up and cool down every single time. No exceptions, no "I'm only doing four miles". It's the cheapest injury insurance available to a runner over 50.
See your GP about anything persistent. Fatigue that doesn't lift. Changed bowel habits. Low mood. Symptoms that worry you. Men are famously rubbish at this, and I speak as someone whose life was saved by getting something checked.
Runna Training Plans for Runners Over 50
Runna builds warm-ups, cool-downs, strength sessions and load management into one plan, which covers most of what this article recommends.
Reading a list like the one above is easy. Building a week that contains strength work, plyometrics, easy miles, some intensity, proper recovery gaps and a warm-up and cool-down every session is where most of us fall over. It's a lot of plates to spin, and spinning them badly is how you end up injured or exhausted. Here's why the app suits a runner of my age specifically.
Every session has a warm-up and cool-down built in. Not an optional extra you scroll past, but part of the session. For a bloke in his 50s whose Achilles need a proper conversation before they'll cooperate, that matters more than I can tell you. It removes the decision, and removing the decision is how a habit survives a wet Tuesday in February.
The strength library is comprehensive. Upper body, lower body, weights, Pilates and yoga. You can do them as standalone sessions or have them built into your weekly programme alongside your running. Given that resistance training is the most effective thing any of us can do about muscle loss and bone density, having it in the same plan as the running is exactly the right way round.
The plan flexes. It's tailored to your goal, whether that's a 10K, a marathon or an ultra, and it manages your load so you're not stacking hard days on top of each other, which, as section 4 covered, is precisely the mistake that catches out runners in their 50s.
That combination of running, strength, mobility and recovery in one place is why I use it. It improves the runner in me as a whole, rather than handing me a set of paces and wishing me luck.
If you want to try it, I've arranged a double-length free trial for readers: two full weeks of Runna Premium instead of the usual one.
👉 Download the app and enter code ANDY2, or use this affiliate link: web.runna.com/redeem?code=ANDY2
Set up your running plan, then go into the strength section and build a couple of sessions into your week. Your 60-year-old self will be extremely grateful.
Running Over 50: Frequently Asked Questions
Is it too late to start running in your 50s?
No. A 2019 study by Piasecki and colleagues comparing masters runners who trained all their adult lives with those who started after 50 found no difference in training intensity or age-graded performance. Start with run-walk sessions three times a week, add two short strength sessions, and increase weekly mileage by no more than 5 to 8%.
How many days a week should a runner over 50 run?
Most runners over 50 do well on three to five running days a week plus one or two strength sessions. Keep hard sessions 72 hours apart rather than 48, make most runs easy, and build weekly mileage by around 5 to 8% rather than the traditional 10%.
How much slower do runners get after 50?
Trained men lose roughly 5% of their aerobic capacity (VO2 max) per decade, about half the 10% lost by untrained men. Untrained men can be 30 to 40% below their peak by their mid-60s. Endurance-trained men in their 60s often record VO2 max scores above the average for men in their 30s.
Why does running get harder as you get older?
Running gets harder after 50 because VO2 max falls by about 10% per decade in untrained people, maximum heart rate drops by roughly one beat per minute per year, and muscle mass declines by 1 to 2% a year. The same pace costs more effort. Trained runners decline at about half that rate.
Does metabolism slow down after 50?
No. A 2021 study in Science by Pontzer and colleagues, measuring more than 6,400 people in 29 countries, found metabolic rate stays stable from age 20 to 60 and then falls by less than 1% a year. Midlife weight gain is more likely caused by muscle loss and falling testosterone.
Why do men over 50 gain belly fat even when running?
Falling testosterone shifts fat storage towards the abdomen, and losing muscle lowers resting energy burn. Research also suggests the body offsets around 28% of the calories burned through activity, so running more rarely shrinks the waist on its own. Strength training, adequate protein and good sleep are more effective levers.
How much protein does a runner over 50 need?
Around 1.0 to 1.2g of protein per kg of body weight per day, according to the ESPEN and PROT-AGE expert groups. That is 80 to 96g a day for an 80kg man, compared with the UK general recommendation of 0.75g per kg. Aim for about 25g per meal, three times a day.
What is a good VO2 max for a man in his 50s?
The median VO2 max for men in their 50s is about 29 ml/kg/min, compared with about 35 in their 40s and 25 in their 60s. Trained runners sit well above these figures, and endurance-trained men can hold VO2 max scores typical of men 20 to 30 years younger.
Is running good for men over 50?
Yes. Running maintains aerobic fitness, which declines about half as fast in trained men, and is not linked to higher arthritis rates at recreational levels. On its own it doesn't prevent muscle or bone loss, so men over 50 get the most benefit by pairing it with twice-weekly strength training.
Can you run a marathon or ultra in your 50s?
Yes. Many runners complete marathons and ultras well into their 50s and beyond, provided they allow longer recovery, build mileage gradually and include strength work. I completed the Tour du Mont Blanc for the second time in my 50s, after cancer treatment.
Does running lower testosterone?
It can, but usually only with very high training volume, chronic under-fuelling or poor recovery. Researchers led by Anthony Hackney call this the "exercise-hypogonadal male condition". Balanced, well-fuelled recreational running is not linked to low testosterone. If you feel flat all the time, review fuelling and recovery first, then see your GP.
Should men over 50 get their testosterone tested?
Only if you have persistent symptoms such as fatigue, low mood, reduced strength or low libido. Your GP can arrange a blood test, usually taken in the morning when levels are highest. Avoid clinics or online sellers offering treatment before a proper diagnosis.
Does running cause arthritis in older runners?
No, not at recreational levels. A 2017 meta-analysis by Alentorn-Geli and colleagues found hip and knee arthritis in 3.5% of recreational runners, compared with 10.2% of sedentary people and 13.3% of elite runners. Only very high-volume, competitive running was linked to higher rates.
How much strength training do runners over 50 need?
Two or three sessions of around 30 minutes a week, according to research on age-related muscle loss. Focus on compound lifts such as squats, deadlifts and lunges, plus calf raises for the Achilles. Schedule them on easy or non-running days.
Why are Achilles tendons stiff in the morning after running?
Tendons lose elasticity with age and need longer to warm up, so mild stiffness that eases within a few minutes is common in runners over 50. Stiffness that lasts, worsens, or hurts during runs can be an early sign of Achilles tendinopathy and is worth seeing a physio about.
How do you stop runner's diarrhoea?
Cut high-fibre and gas-producing foods for about 24 hours before a long run or race, limit caffeine and fat beforehand, avoid anti-inflammatories, stay hydrated, and wear kit that isn't tight at the waist. Rehearse race-day fuelling in training. See your GP if a change in bowel habit persists.
Is running good for bone density in men?
Yes, but only partly. Running is weight-bearing and stimulates bone formation, but the load is lower than from lifting or high-impact work, and high mileage with under-fuelling can reduce bone density. Adding strength training and plyometrics or hill sprints gives bones a stronger stimulus.
Running in Your 50s: The Bottom Line
Running in your 50s is harder than at 35, but strength work, sensible recovery, proper fuelling and consistency can roughly halve the rate of decline. Pretending your body hasn't changed is how runners get hurt. The tiredness is real. The tight Achilles are real. The hedgerow situation is, regrettably, extremely real.
But the research is remarkably consistent on one point: how quickly these things progress is largely down to what you do about them.
I'm not chasing PBs any more. I'm chasing another 25 years of lacing up. On the evidence, that's a far better goal anyway.
If any of this rang a bell, drop me a comment or a message. I'd love to know I'm not the only one negotiating the stairs with three cats and a bannister at 5am.
Lace up and enjoy your miles.
This article shares my personal experience and publicly available research. It is not medical advice. I'm a runner, not a doctor. If you're experiencing symptoms that concern you, please speak to your GP.
About the Author: Andy Hood
Andy Hood is an ultra and endurance runner, cancer survivor and advocate for men's health. After a diagnosis tried to take his running shoes off, he laced them back up and turned the experience into a mission: designing bold, attention-grabbing ultras each year to raise awareness and funds, particularly for testicular cancer. He has raised over £28,000 for charity to date.
That mission includes his cheeky-but-serious menswear brand, Check Ya Balls: kit with a message that quite literally saves lives.
Follow his runs, read his race reports, and grab a pair of Check Ya Balls at runningwestwardho.co.uk.
Comments