Your man has another woman you don't know about. Her name is Strava.

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Where once upon a time a man's 40th birthday heralded in fears about sports cars and affairs at work, there's another type of marital disquiet hitting couples in midlife.

While it might not be as catastrophic as the idea of infidelity, households across Australia are dealing with a new type of midlife cheating: the husband hobby.

"I checked the account balance and discovered he'd spent $500 on a single golf club," a girlfriend confided, evidently exasperated. 

"Two weeks beforehand, he told me a weekend away for our anniversary was outside the budget, but I'm just supposed to swallow this?"

Watch: The hosts of But Are You Happy? on relationships when you can't seem to agree. Post continues below.

"We used to cycle the sleep-ins on the weekend," another chimed in.

"I'd take the kids' breakfast shift on Saturdays, he'd take Sundays, so at least we got one responsibility-free morning per week. Now that he's joined his bloody run club, he's up and out the door at 5am both mornings, for at least three hours each time.

"He might be willing to give up his own weekend sleep-ins, but he's given up mine as well!"

Another friend told me at the school gate that her husband is training for a marathon. 

"I know I should be supportive, but it's about 10 additional hours of running per week," she said, "all while I've had to cancel my last three Pilates classes because of commitments with the kids."

There's no denying that the midlife male hobby market has exploded in recent years, particularly in the area of running.

Globally, fitness app Strava reported a 59 per cent rise in run club participation in 2024, with a post-pandemic drive for more fitness and community in men aged 34-55 credited for much of this push.

And it's become a stereotype for a reason: many men of a certain vintage — particularly those who decide to put down the schooner in favour of a pair of Nikes — the pull towards developing a running habit is a milestone as common as finding your first grey beard hair or deciding to switch over to Double J from its younger, more popular cousin. 

All around me, friends' husbands are running 10, 20 or even 30 kilometres on a regular basis — or else they're mountain biking in Tasmania, or spending hours on the golf course. 

And overall — how good?! We hear constantly about the male loneliness epidemic, so anything that encourages men to socialise away from the pub and stay active is undoubtedly a net positive.

Except when that new hobby, as is often the case, becomes yet another unevenly-balanced brick on the mental load of his female partner. 

Because while men in midlife might be finding endless hours in the schedule to dedicate to their new passions, women in midlife are generally busier than they've ever been. 

Worldwide, women spend an average of two to 3.4 times as many hours per day as men on unpaid work (like cooking, cleaning, and caring for children and the elderly).

For women, according to this World Bank data, getting married and having children generally means more unpaid childcare and domestic work and less leisure time on average. For men, it often means more time for leisure and earning money in the marketplace.

So is it any wonder that, for many women, the advent of a new hyperfixation for their partner comes not with a sense of relief and vicarious happiness, but with the sinking sense that they're somehow going to have to make up the shortfall around the house?

"The imbalance it creates."

"When one partner (and I hate to say it, but often men in midlife) becomes consumed by an endurance hobby like running, cycling, or golf, it can start to erode the couple's bond," explained Julie Sweet, psychotherapist and clinical counsellor at Seaway Counselling and Psychotherapy. 

"The activity itself isn't the problem, it's generally the imbalance it creates in time, attention, and emotional availability."

Sweet says researcher Stan Tatkin's work on 'thirds' and marriage counsellor John Gottman's decades of research on the 'couple bubble' both highlight how relational safety, shared meaning, and emotional presence are what sustain connection over time.

"Tatkin describes a 'third' as anything that draws energy away from the relationship," she explained. 

"That 'third' could be work, a child, screens, an ex — or in this case, Strava. When one partner spends increasing hours training or tracking stats, the other can feel abandoned or resentful, particularly when they're juggling household and emotional labour.

"It can, for some, start to feel like an affair – elements like secrecy, withdrawal, withholding, obsession, and a sense of exclusion may present."

And while Sweet acknowledges that fitness is one of the most potent tools in the mental health first aid kit for a cohort of humans (men in midlife) particularly susceptible to mental ill-health, she advises more open communication — and some give-and-take — when it comes to launching into a new, time-consuming hobby with both sneakered feet.

"The goal isn't to eliminate the hobby or to control the other person, but more to bring it into the relationship – to put the cards on the table," she said. 

"The question for the partnership becomes — can this be shared, supported, or at least scheduled collaboratively?"

Navigating this stage.

Sweet says couples who navigate this stage well often:

• Negotiate time consciously — treating training or golf hours like any other commitment, with mutual consent and transparency. "They literally sit down weekly with shared family calendars and carve out time to have schedules align," she said. "Successful couples also map out (again literally) dealbreakers, negotiables and so on."

• Prioritise rituals of connection — even brief check-ins or moments of affection that remind each other that 'you still come first.' "It might sound corny or overkill, yet daily check-ins are what create a secure functioning relationship," Sweet said. "Consciously working on the relationship each day is what causes a partnership to grow and be protected."

• Revisit the meaning of these pursuits. "Is it about escape, avoidance, identity, or something else? Understanding the "why" helps partners find empathy and create the capacity to combine their needs rather than merely compromise," she continued. "A couples' therapist once told me that 'blending' is a better word than 'compromise,' and that has always stayed with me."

And ultimately, we all want our partners to live happy and fulfilled lives, being able to pursue their passions. 

Listen to Mamamia Out Loud. In this episode, hosts Em, Claire and Holly discuss the need for a 'shobby'. Post continues below.

We'd just like to have that same luxury afforded to us — and the sad reality for many women is that the burden of family admin simply doesn't allow for it. 

As my 'marathon widow' friend said drily at the school gate last week, staring down the barrel of another night doing dinner and bathtime solo while her husband clocked up the kilometres: "It's nearly made me want to sign myself up for a marathon just to get the same amount of time away from home.

"I think 42km might actually be less work than being the other partner holding down the fort!"

Feature image: Google Gemini.