Why your 30s and 40s can be the perfect time to start running

As a child growing up in Ireland, Sinead Diver was always sporty, playing basketball and soccer. But it wasn’t until she moved to Australia at 25 to go backpacking with her now-husband that she started running – a sport she was first drawn to because it seemed like the cheapest way to get fit.

Years later, when Diver’s sister asked her to join in a corporate fun run, she realised she was quite good at running. Today, Melbourne-based Diver is one of three Australian female marathoners who have qualified for the 2024 Olympics, heading to Paris alongside Genevieve Gregson, 34, and Jess Stenson, 36.

“When I turned 38, I went to my first world champs,” says the now 47-year-old. “At the time, I thought that might be my last one, given the general view that once you’re in your 30s, you’re kind of past it athletically.”

Sinead Diver ahead of the 2023 Sydney Marathon.Credit: Brook Mitchell

What is obvious now, looking back on that time, is that Diver’s journey was just beginning. Along with her success came a rethinking of what she once assumed about women’s “peak” age and endurance running.

Kotryna Fraser, an exercise and sport science lecturer within the Faculty of Medicine and Health at the University of Sydney, says men and women can perform better at endurance sports in their 30s and 40s than in the decades earlier.

“Sports are classified in different categories because they require a different type of effort and different types of energy systems,” says Fraser. “There’s a massive difference between endurance events and strength events. When you look at any strength event, both males and females peak at younger ages.”

While our strength declines as we age, making events that rely on power more difficult, endurance events such as marathons require sustained training. This training time can be easier to accumulate the older we are.

Fraser says that while being older doesn’t necessarily mean we will be better runners than we might have been in our youth, there is evidence to suggest that our mental resilience – an important skill in endurance events – could improve as we age and experience more significant life events, which help us fine-tune coping skills.

“Mental resilience is a huge part of any athletic pursuit, but particularly for the marathon because it’s such a long event,” says Diver. “There’s so much thinking time, when all these fears and doubts can infiltrate your mind.”

Sinead Diver will be competing at the 2024 Paris Olympics.

This is where Diver considers her late start to the sport an advantage. “Before I started my athletic career, I had a whole other life – I was working, I was a mum – so running was never the be-all and end-all,” she says. “It’s important to me, but there are other things in my life that are important as well.”

This perspective is incredibly valuable, especially for female athletes who can be prone to burnout and relative energy deficiency in sport (REDs), which is caused by a lack of balance between the energy demands of exercise and the energy from food provided to the body.

For Nike Pacific run coach Lydia O’Donnell, it wasn’t until her late 20s that she came to understand how to look after her body, from proper nutrition to training around her menstrual cycle. After taking a break from running due to being diagnosed with REDs, O’Donnell spent two years rethinking her training and getting to know her body and its needs.

Today, the 34-year-old former New Zealand national champion is passionate about helping women of all ages get excited about running and learning how to look after themselves and train sustainably. O’Donnell is also a huge proponent of people who menstruate tracking their cycle as it’s been a game-changer for her training and journey to recovery. “There is so much more to our cycle than just when to get pregnant and when to not get pregnant,” she says.

“In our sport, the system is set up for athletes to thrive in their early 20s, even though there are so many incredible athletes in their 30s and 40s right now,” says O’Donnell. “I hope the system catches up.”

Starting running professionally later than many women, Diver says she’s never had the pressure to be a certain weight, which can end the careers of many female athletes. “If a coach said that to me, I have the strength to stand up to it,” she says. “I’m more certain about myself now than I was when I was younger.”

For anyone considering taking up running, Diver says the worst thing a person can do is allow society’s limitations hold them back.

“If I listened to people when I started out, I would have never gotten this running career.”

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