Jason Smith spent his late 40s sedentary, overweight, and unfulfilled — until a moment of inspiration changed his life.
Today, at 56, he’s a marathon runner, personal trainer, and the founder of Fit in Midlife, a movement helping thousands redefine what aging looks like.
His story offers more than inspiration — it’s a roadmap for anyone looking to reclaim their health, energy, and self-worth later in life.
From ditching the desk job to running a sub-4-hour marathon, Smith’s journey proves that it’s never too late to get strong, fit, and even launch a new career.
His transformation didn’t rely on shortcuts or extreme workouts. Instead, it was built on three core principles — and a walking habit that he believes can change lives.
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From Burnout to Breakthrough
Before 2019, Smith lived what many would consider a “normal” life: long hours at a corporate desk, ultra-processed microwave meals, no regular exercise, and declining mental and physical health.
“I was overweight to the point of obesity, unwell, and in a pretty bad way physically and mentally,” he told Business Insider. But a single social media post turned things around. It wasn’t a before-and-after photo or a flashy fitness ad. It was an image of Bilbo Baggins running through the Shire with the quote: “I’m going on an adventure.”
That one moment “flicked a switch” in his mind. He pulled on a pair of trainers and went for a walk in the Surrey Hills — the first step of a new journey.
1. Set a Clear and Personal Goal
Before lifting a single dumbbell, Smith got his mindset in check. He visualized his “ideal self” and wrote two lists: one with actions he would take, and another with those he wouldn’t.
“The first thing that I did was get my mind in the right place,” he said. “Having that vision in my head and almost this plan of what I would and wouldn’t do really, really helped.”
Visualization techniques, backed by neuroscience, have been shown to improve decision-making and boost emotional resilience. For Smith, it helped him stop quitting whenever life got busy — a pattern he’d fallen into many times before.
2. Find the Fun in Movement
“You’re not going to do anything you don’t enjoy,” Smith says — and science agrees. Studies have shown that people who enjoy their workouts are more likely to stick with them long term.
Instead of forcing himself onto a treadmill, Smith revisited what he loved as a child: running through the woods. So that’s where he started — literally. The joy he felt made workouts something to look forward to.
By April 2022, he ran his first marathon in under four hours.
3. Start Slow — and Stay Consistent
Smith didn’t dive into extreme fitness challenges. He committed to just one hour of movement per day. In the beginning, it was mostly walking, with “occasional running spurts.”
At the gym, he focused on foundational movements like lunges and squats. A beginner session with a personal trainer helped him learn proper form and avoid injury.
“It’s not how hard you work in the hour,” he said. “It’s how many times you do that.”
That simple but powerful truth laid the foundation for a sustainable routine — one that would become his second career.
How Walking Sparked a Fitness Revolution
Walking was the gateway. Not just for Smith, but for many of the clients he’s coached since launching Fit in Midlife during lockdown. “Walking is the most underrated form of exercise,” he says.
He’s seen clients drop over 20 pounds, normalize their blood pressure, and completely change their lifestyles — all by building a regular walking habit.
Here’s why he says walking is so powerful:
1. It Burns Fat — Especially the Dangerous Kind
“Walking raises the heart rate into fat-burning zones while preserving muscle mass,” says Smith. That makes it ideal for sustainable weight loss — especially in midlife, when muscle loss is more common.
He shares the story of Johnny, a client who averaged 1kg (2.2 lbs) of weight loss per week by simply meeting a daily step goal and improving his diet.
2. It Boosts Mental Clarity and Emotional Health
“It’s a fantastic way to clear the mind,” says Smith. “I treat every walk as an adventure.”
He often practices ‘adventure walking’ — exploring new trails or streets just to see what’s out there. It keeps the activity fresh and engaging, whether in the countryside or the city.
3. It Deepens Relationships
From walking clubs to catch-ups with friends, walking creates space for meaningful connection. “Walking meetings” aren’t just for Silicon Valley — Smith encourages them as a tool to improve personal and professional communication.
One of his clients now walks the UK’s most iconic trails with his daughter. It’s their shared passion, and something neither imagined possible before.
4. It Improves Overall Health — Inside and Out
The health ripple effect is real: reduced blood pressure, better cholesterol, improved cardiovascular fitness, enhanced immunity, and increased energy. Smith sees this in client after client.
“You feel lighter and more energized,” he says. “You do more, and think more clearly.”
5. It Improves Sleep Quality
Walking promotes deeper, more restorative sleep by regulating stress hormones and physical fatigue.
“It leads to a reduction in insomnia or restlessness,” says Smith. “You wake feeling ready for the day.”
The Birth of Fit in Midlife
After qualifying as a personal trainer at age 50 — a birthday gift from his family — Smith started teaching classes on Zoom during lockdown.
He quickly realized the fitness industry wasn’t built for midlifers. Most personal trainers were decades younger. “When you’re in your late 40s, 50s or 60s, the body works differently,” he explained.
He developed programs with slower tempos, lighter weights, and proper recovery to accommodate older joints and muscles. The approach resonated — today, he trains clients between 40 and 70 years old, both in-person and through his new fitness app.
A Client Doing Press-Ups on the Deck of His Life
Smith remembers one client in particular — a man in his 60s who served in the Royal Navy. After months of training, he completed 20 full press-ups.
“He looked at me and said, ‘You know, I haven’t done press-ups like this since I was on the deck of the HMS Ark Royal in my 20s.’”
Stories like these are what fuel Smith’s mission. “It’s so rewarding when you get people to do things they never thought possible.”
The “Midlife Movement” Vision
Smith’s long-term goal is simple but ambitious: inspire people over 40 to get active and reclaim their vitality.
According to a 2025 UK government report, fewer than 1 in 3 people over age 40 are a healthy weight. Smith believes this isn’t due to laziness or lack of willpower — but a lack of belief that change is possible.
His message is clear: “You can do this. It’s not too late. The life you want is still in front of you — you just have to take that first step.”
Where to Find Jason Smith
To follow Jason’s work, visit www.fitinmidlife.com or find him on social media @fitinmidlife. His app offers customized workouts, meal plans, and support for midlifers ready to make a change.
Whether you’re 40 or 70, his story offers a powerful reminder:
Your second act can be your strongest — you just have to start walking.
