Welcome to Plus50Fit, my ongoing experiment in running after 50, staying active and discovering what this body can still do.
I’m Magnus, a 67-year-old recreational runner who didn’t always love running. Before 2018, I was a committed winter couch potato. I’d gain a few pounds, hibernate indoors and regard long-distance running as something other people inexplicably chose to do.
Then I challenged myself to break the cycle.
How I Got Here
In 2018, I joined a Learn to Run program, laced up my shoes and headed outside. That first winter taught me two important things: I wasn’t going to freeze to death, and I was capable of more than I thought.
First came 5K. Then 10K. Then the half marathon.
Eventually, I started thinking about a marathon.
My first marathon attempt at the 2025 TCS Toronto Waterfront Marathon didn’t end at 42.2 kilometres. Course flooding and the cutoff ended my day at 35 kilometres. It wasn’t the finish I’d imagined, but it became part of the real story this site exists to tell.
Running after 50 hasn’t been a tidy progression from one triumph to the next. I’ve had strong races, disappointing races, injuries, interruptions, comebacks and more than a few mornings when ambition and readiness clearly hadn’t spoken to each other.
Still, I’m running.
What I’m Training for Now
My current goal is the BlackToe Holiday 10K in December 2026. I’ll be 68 by race day.
The plan after BlackToe is to spend 2027 focusing on 10Ks and half marathons. Then, if health and circumstances cooperate, I want to run a fall marathon in 2028 as a celebration of turning 70.
That’s my Road to 70.
The longer horizon has changed how I think about training. I’m still interested in improving, racing and discovering what kind of performance remains possible. However, I’m also trying to preserve the consistency that will let me keep doing this for years.
The next workout matters. So does the runner I’m hoping to be at 70.
The Plus50Fit AI Running Coach Experiment
One of the central projects on Plus50Fit is my AI Running Coach Experiment.
I’m not asking ChatGPT to produce a generic training schedule and then blindly following it. I’m building an ongoing coach-and-runner workflow that connects each prescribed workout to what actually happened.
The system can include:
- My recent training history
- My current race goal and available training days
- Individualized heart-rate zones
- Garmin FIT activity data
- Pace, heart rate, cadence, laps and pauses
- Weather and terrain
- Sleep, fatigue, soreness and readiness
- My pre-run expectations
- My post-run RPE and observations
- The original workout compared with its actual execution
- Previous assessments from the same training block
Each workout receives a persistent run ID. That ID connects the coach’s prescription, the Garmin activity, data from my Plus50Fit FIT Tool, my personal context and the resulting assessment.
You can start with How I Use ChatGPT as My AI Running Coach at 67. That article explains the complete experiment, including what I think AI does well, where it can go wrong and why human judgment remains necessary.
BlackToe gives the experiment a real finish line. I’ll document the prescriptions, completed sessions, adjustments, mistakes, questionable data and race result. Then I’ll assess whether the system was useful enough to continue.
This is an N=1 case study, not scientific proof. I’m one runner testing one evolving approach through one training block.
Data Matters, but So Does the Runner
I enjoy running data. I’m interested in heart rate, pace, cadence, aerobic efficiency and how one workout compares with another.
But numbers don’t know everything.
Garmin may know that my heart rate increased. It doesn’t automatically know that I slept poorly, felt an ache, encountered unexpected heat or deliberately backed off. On the other hand, how I remember a run isn’t always supported by what actually happened.
That’s why I want both.
My Training Metrics Made Simple guide explains many of the numbers I use. Meanwhile, the AI experiment explores what happens when those numbers are combined with the runner’s experience instead of being treated as the whole story.
Strength, Recovery and the Long Game
Running after 50 involves more than running.
I also write about strength, mobility, recovery, injuries, nutrition, blood pressure, gear and the strange negotiations that happen between a determined brain and an aging body.
My minimum strength training framework for older runners grew from a simple question: what movement abilities do I need to keep supporting without turning strength training into another full-time occupation?
The result was a seven-movement audit built around pushing, pulling, squatting, hinging, stepping, springing and bracing. It isn’t a universal prescription. It’s a practical way to see what my existing routine covers and what may be missing.
My Ouch to 10K pivot tells the other side of the story. Sometimes the most intelligent training decision is to stop forcing the original plan and build another route forward.
Food Still Has to Taste Like Food
Nutrition has become another important part of Plus50Fit.
I take prescribed blood-pressure medication, exercise regularly and have reduced weight through changes in activity and nutrition. However, the most striking improvement I noticed in my own blood-pressure readings came after I adopted a no-added-salt, generally lower-sodium way of eating.
That’s my observation, not proof that one change caused everything.
When I cook, I don’t add salt, potassium-chloride substitute or MSG. Instead, I use acidity, aromatics, spices, browning, fat and texture to make food taste complete.
P50Fit Recipes will collect the meals I actually cook, including nutrition estimates, sodium traffic-light verdicts and downloadable recipe cards. The goal isn’t bland medical-diet food. Dinner still has to taste like dinner.
What You’ll Find on Plus50Fit
I use Plus50Fit to share:
- Training plans, workout assessments and race preparation
- The AI Running Coach Experiment
- Garmin data and training metrics explained in ordinary language
- Strength and mobility for older runners
- Injury, recovery and comeback stories
- Race reports, including the parts that didn’t go according to plan
- Nutrition, blood-pressure-conscious cooking and P50Fit Recipes
- Gear, software and tools that support the process
- Honest reflections on fitness, aging and motivation
I’m not a running coach, physician, physiotherapist or dietitian. I’m an experienced recreational runner documenting what I try, what happens and what I learn.
AI helps me research, organize, analyze and draft some of this work. I review, correct and approve what appears here based on my records and lived experience. AI can help me ask better questions, but it can’t diagnose an injury or replace an appropriate human professional.
Keeping It Real
I don’t want Plus50Fit to become a victory-reel version of aging.
Some workouts feel wonderful. Some feel like unpaid labour. Sometimes the data reveals progress. Sometimes it reveals that I was confidently wrong.
That’s all part of the experiment.
I’ll share the highs, the lows, the pivots, the occasional “quick thought” and the moments when the Dreadmill and I are forced into another reluctant reunion.
My working belief is simple:
I get to do this. I can do this.
The goal isn’t to pretend age doesn’t matter. It’s to remain curious about what’s still possible.
Join the Journey
Follow along as I train for BlackToe, test the AI coaching system and continue along my Road to 70.
You can:
- Follow me on Instagram at @plus50fit
- Subscribe for new Plus50Fit articles
- Explore the AI Running Coach Experiment
- Leave a comment and share what you’re working toward
Whether you’re returning to exercise, chasing another finish line or simply trying to remain strong and useful, you’re welcome here.
See you on the road, or perhaps on the Dreadmill when the weather isn’t cooperating.