Day 34 of 300: The Half Marathon Question

I ran 6.7km today. Longest single run since late January. Then I made the mistake of asking my fitness trainer whether a half marathon in December was realistic.

He didn’t sugarcoat it.

The run

• Distance: 6.72 km
• Time: 48:00
• Pace: ~7:09 /km
• Heart Rate: 148 bpm (avg) / 175 bpm (max)
• Calories: 723 kcal
• Steps: 7,582
• Training Load: 227

The longest treadmill run I’ve done this year. Average heart rate of 148 means I spent most of this in zone 3 and above. Max of 175 is close to my ceiling. For a “base” run, the effort was high. The body was working hard to move this weight at a jogging pace. Training readiness started the day at 55. After this session it crashed to 9. Recovery estimate: 47 hours.

The question

I’ve been thinking about signing up for a half marathon in December. 21.1 kilometres. Nine months away. It feels like a good goal for this 300-session project, something concrete to train towards instead of just accumulating days.

So I asked. And here is roughly what I was told, minus some of the profanity.

What the trainer said

**"Your VO2 max is 38.7.  Garmin predicts you'd finish a half marathon in 2 hours and 32 minutes.  That's an 11:37 per kilometre pace.  Parts of that would be walking.  You can do better than that, but not by accident."**

He pulled my running history for the year. This is where it got uncomfortable.

Fifteen sessions in January. One in February. He called February “a disappearing act” and asked if I was planning another one. Fair question. I don’t have a good answer.

**"A half marathon plan needs you running three to four times a week, consistently, for months.  You haven't shown you can hold three times a week for more than a few weeks before dropping off.  The fitness is buildable.  The question is whether you'll still be running in May."**

The weight conversation

This is the part I knew was coming.

Last weigh-in: March 13. 111.3 kg. That was 16 days ago. BMI: 33.3. Fitness age: 44 against my actual age of 43, and Garmin says the achievable fitness age is 37.1 if I sort the BMI out.

**"Every kilogram above race weight costs you roughly two seconds per kilometre.  At 111 kg you're hauling a backpack into a half marathon.  No amount of interval training fixes that.  Weight is the single biggest lever you have between now and December."**

He’s right. The fitness age breakdown is clear about this. BMI is priority one. If I fixed BMI alone, fitness age drops from 44 to 38.5. The other components, vigorous minutes and resting heart rate, are already in a decent place. RHR is 60 bpm. Vigorous minutes averaging 63 per week against a target of 75. Those are fixable with consistency. The weight requires something more deliberate.

**"Get on the scale.  Today.  And every week from now on.  You can't manage what you don't measure, and you haven't measured in over two weeks."**

The load ratio warning

Today’s session pushed the acute-to-chronic load ratio to 1.5x. That’s the red line. Acute load of 448 against a chronic of 295. ACWR status: HIGH.

This is only one week after the football match blew it to 2.8x. It had been recovering nicely, down to healthy levels by Thursday. Then today’s 6.7km session, combined with the football, squash and pickleball from the past week, pushed it back up.

**"You're right on the edge of overreaching again.  And this is after a week with only one actual run.  Your body isn't conditioned for what you're asking.  The engine is willing but the chassis isn't ready."**

The sleep problem

He pulled the last eight nights.

Average score: 64. Sleep history factor in training readiness: 32%, rated POOR. That 2.8-hour night on the 27th dragged the whole week down. REM sleep has been consistently low. Last night was 8.1%. Should be above 20%.

**"Sleep is the foundation.  If sleep is bad, nothing else matters.  You can't outrun bad sleep.  Your sleep history is the single worst factor in your training readiness.  Fix this or accept that your training is going backwards."**

The prescription

Here’s what he told me to do between now and December.

Now through June: Build the running habit. Three runs per week, every week, no excuses. Start at current distances (3-5 km) and add no more than 10% per week. Keep most runs easy. Heart rate below 140. The goal is not fitness, it’s consistency.

Weight: Get below 100 kg by September. That’s roughly 11 kg in six months. Half a kilogram per week. Achievable with consistent training and basic nutrition discipline. Weigh in every week. No gaps.

Sleep: Seven hours minimum, every night. Consistent bedtime. No screens before bed. This isn’t a nice-to-have. It’s the platform everything else sits on.

July onwards: Start a structured 16-20 week half marathon plan. By then I should be running 25-30 km per week comfortably. That’s the base from which you build long runs, tempo sessions, and race-specific work.

The target: Sub-2:15 if I do the work. Sub-2:00 if I also lose the weight. Current prediction of 2:32 assumes nothing changes.

The bright spots

He did acknowledge some things. HRV factor is 100%, rated VERY GOOD. The autonomic nervous system has capacity. Resting heart rate trending down. Stress management is solid, 62% rest today, average stress level of 28. The training status is PRODUCTIVE, which means the body is responding to the load it’s receiving, even if the load isn’t well managed.

“The engine is there. The HRV says your body can handle more. The question isn’t capacity. It’s whether you’ll show up consistently enough to use it.”

What I think

He’s right about all of it. The consistency problem is real. February was a write-off and I can feel how much ground I lost. The weight is the obvious lever and I’ve been avoiding the scale because the number doesn’t move as fast as I’d like.

But today I ran 6.7 km without stopping. In January I was doing run-walk intervals to get through 5 km. The pace isn’t fast but the endurance is building. The cross-training, squash, football, pickleball, is doing something even if it isn’t structured. The body is fitter than it was on Day 1.

December is nine months away. That’s a lot of sessions. A lot of early mornings. A lot of opportunities to disappear for another February.

The difference between finishing a half marathon and not finishing one isn’t talent or genetics. It’s showing up three times a week for nine months. That’s it. That’s the whole challenge.

Day 34 of 300. 6.7 km. The longest run of the year. A half marathon is four times that. Time to close the gap.

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