Is 37 Too Old to Start Running? Here’s What Actually Happens When You Begin After 35

You’re 37. Maybe you’ve been sitting too long at your desk. Maybe your jeans don’t fit like they used to. Or maybe you saw a friend cross a marathon finish line and thought, Could I do that? Then comes the doubt: Is 37 too old to start running? The answer isn’t a simple yes or no. It’s not about your age-it’s about your body, your plan, and your patience.

Your body at 37 isn’t broken-it’s just different

People say your 30s are when things start to slow down. That’s not entirely true. Your metabolism might shift a little. Recovery takes longer. Joints aren’t as springy as they were at 22. But here’s what no one tells you: your muscles still grow. Your heart still strengthens. Your lungs still adapt. A 2023 study from the Journal of Sports Sciences found that adults who started running between ages 35 and 45 improved their VO2 max-how well your body uses oxygen-by an average of 18% in just six months. That’s the same gain many 20-year-olds see. Age doesn’t lock you out. It just changes the rules.

At 37, you’re not starting from zero. You’ve got life experience. You know how to listen to your body. You’ve probably dealt with injuries before. That’s a huge advantage over a 20-year-old who thinks pain means they’re making progress. You know when to rest. You know when to push. That’s not something you can buy at a gym.

Marathon training? Yes. But not like you think

Can you train for a marathon at 37? Absolutely. But you won’t follow the same plan as a 22-year-old who just graduated college. The mistake most beginners make is copying online programs designed for people in their 20s. Those plans assume you can run four days a week, recover overnight, and handle 12-mile long runs without a second thought. At 37, that’s a recipe for burnout-or worse, injury.

Realistic marathon training after 35 looks like this:

1. Start with walking and jogging intervals-5 minutes jogging, 2 minutes walking. Repeat for 20-30 minutes, three times a week.
2. After four weeks, increase jogging to 8 minutes, walking to 1 minute. Keep it to three runs per week.
3. Every third week, take a full rest week. No running. Just walking or stretching.
4. Build your long run slowly. Add one mile every two weeks. Don’t go beyond 16 miles before your marathon, even if the plan says 20.
5. Strength train twice a week. Focus on hips, glutes, and core. Squats, lunges, and planks are non-negotiable.

Most people who finish their first marathon after 35 do it in 5 to 6 hours. That’s not slow. That’s smart. You’re not racing the clock-you’re racing your past self.

The real enemy isn’t age-it’s inconsistency

People who quit running after 37 aren’t quitting because they’re too old. They’re quitting because they tried too hard too fast. They ran five miles on day one. Got sore. Didn’t feel like a hero. Quit. Then they tell themselves, See? I’m too old for this.

It’s not about how far you run. It’s about showing up. Even if it’s just 15 minutes. Even if you walk half of it. Even if you’re tired, stressed, or it’s raining. Consistency beats intensity every time after 35.

Think of it like learning a language. You don’t become fluent by cramming for 3 hours once a week. You become fluent by speaking 10 minutes a day. Running works the same way. A 20-minute run three times a week will change your health more than a 10K once a month.

What changes when you start running after 35?

It’s not just about losing weight or running faster. The real shifts are quieter-and more powerful.

• Your sleep improves. A 2024 study from the University of Adelaide tracked 200 adults over 35 who started running. After 12 weeks, 72% reported deeper, more restful sleep-even if they didn’t change their bedtime.
• Your mood steadies. Running boosts endorphins and serotonin. For people dealing with stress, anxiety, or mild depression, this isn’t a bonus-it’s medicine.
• Your confidence grows. You start believing you can do hard things. That spills over into work, relationships, and other goals.
• Your body becomes more resilient. Bone density increases. Tendons strengthen. Your body learns how to repair itself better.

One man I know, 41, started running after his dad had a heart attack. He didn’t care about speed. He just wanted to be around for his kids. Two years later, he ran his first half-marathon. His doctor told him his cardiovascular age was now 28.

What to watch out for

Starting out after 35 is safe-but not risk-free. Here’s what to avoid:

• Running every day. Your joints need recovery. Three to four days a week is plenty.
• Ignoring pain. Sharp pain? Stop. Dull ache? Rest. Don’t push through joint pain. It’s not a badge of honor-it’s a warning.
• Buying the cheapest shoes. Your feet carry your whole body. Get fitted at a running store. Spend $120-$150. It’s an investment, not an expense.
• Comparing yourself to others. Social media is full of 25-year-olds running sub-4-hour marathons. That’s not your goal. Your goal is to finish. To feel better. To be alive.

Also, get a basic check-up before you start. Not because you’re old-but because you’re smart. A simple blood pressure and heart rhythm check can catch things you wouldn’t feel until it’s too late.

It’s not about becoming a runner. It’s about becoming more you.

Running at 37 isn’t about chasing youth. It’s about reclaiming control. It’s about proving to yourself that you can still grow, still change, still challenge your limits. You don’t need to run fast. You don’t need to run far. You just need to keep moving.

Every step you take after 35 is a quiet rebellion against the idea that your best years are behind you. And that’s worth more than any finish line.

What’s next?

If you’re thinking about starting, don’t wait for Monday. Don’t wait for the new year. Don’t wait until you feel ready. Start tomorrow. Lace up your shoes. Walk out the door. Run for five minutes. Walk for two. Do it again next day. That’s all it takes.

You’re not too old. You’re just getting started.