Running

Why I Track My Weekly Runs Against the WHO Activity Guideline

July 12, 2026 · by Brendon Kennedy

I run a modest amount — 2 to 4 miles a week, nothing heroic — and I’ve started scoring each week as a single percentage against a public-health benchmark instead of chasing pace or distance PRs. This post is just the methodology: what I measure, the arithmetic, and the rules I hold myself to so the number stays honest and never quietly turns into a health claim it can’t support.

The benchmark: WHO’s 150 minutes

The anchor is the World Health Organization’s 2020 physical-activity guideline. For adults 18–64, WHO recommends at least 150–300 minutes of moderate-intensity aerobic activity, or 75–150 minutes of vigorous-intensity, or an equivalent combination each week, plus muscle-strengthening on two or more days. I use the bottom of that range — 150 moderate-minutes — as my “100%.” It’s the floor most people cite, and treating the floor as the target keeps the bar honest rather than flattering.

Why this guideline and not some fitness-app ring? Because it’s the number with outcome evidence behind it. WHO’s own fact sheet notes that people who are insufficiently active have a 20% to 30% higher risk of death than those who are sufficiently active, and it ties regular activity to lower all-cause mortality, cardiovascular-disease mortality, and several site-specific cancers. A 2023 dose–response meta-analysis in the British Journal of Sports Medicine, pooling 94 cohorts and more than 30 million people, put a number on it: at roughly 150 moderate-minutes a week, all-cause mortality risk was about 31% lower (RR 0.69) and cancer mortality about 15% lower (RR 0.85) versus no activity. Those are the association numbers I benchmark against — with heavy caveats I’ll get to.

The math

Two rules make the arithmetic work.

Convert intensity, don’t ignore it. Running usually isn’t “moderate.” By the talk test — you can talk but not sing during moderate activity, and can’t manage more than a few words during vigorous — most of my run sits in the vigorous band, which the CDC lists running under. WHO’s own numbers say 75 vigorous minutes equal 150 moderate ones, so one vigorous minute is worth about two moderate-equivalent minutes. I convert every session into moderate-equivalent minutes: honest moderate effort counts 1×, genuinely vigorous effort counts 2×.

Then it’s one division. Weekly score = moderate-equivalent minutes ÷ 150 × 100.

A worked week: say a 3-mile run at a 10-minute-mile pace is about 30 minutes. If I was breathing hard enough to fail the talk test, that’s vigorous — 30 × 2 = 60 moderate-equivalent minutes, or 40% of the 150 floor from one run. Two of those in a week is 80%; three tips me over 100%. If a run was an easy conversational jog, I count it 1× and it earns half as much. That asymmetry is the point: it stops me from inflating an easy week.

The honesty rules

This is where a tidy metric can go wrong, so I keep four rules taped to it.

1. It’s a compliance score, not a risk score. The percentage says how much of a population guideline I personally hit this week. It says nothing about my odds of anything. I never read “I hit 90%” as “I cut my own mortality risk by some amount.”
2. Population association is not personal causation. Every mortality and cancer figure above comes from cohort and observational studies. They adjust for confounders but don’t randomize, so they show that more-active populations die at lower rates — not that a given week of mine changed my personal fate. The BJSM analysis is an association, full stop.
3. Cancer claims stay specific and hedged. The evidence links activity to lower risk of particular cancers in observational data — not “prevents cancer.” I won’t write the shorter, wronger sentence just because it fits on a chart.
4. The number is an estimate, so I round down. The intensity call is a subjective talk-test judgment, and the dose–response curve flattens — the BJSM data shows the biggest gains landing by about that first 150-minute chunk, with diminishing returns after. So more isn’t linearly better, and when I’m unsure whether a run was truly vigorous, I log it as moderate.

What I’m actually doing

• Logging every run’s minutes and an honest intensity flag (moderate/vigorous) the same day, in whatever I’m actually keeping the log in that week — the tool matters less than writing it down before I’ve talked myself into a rosier version of the effort.
• Scoring the week with that one division and recording the percentage, floor and all — plenty of weeks land well under 150 moderate-equivalent minutes, and the point is to see that plainly instead of rounding it up in my head.
• Watching the trend, not any single week: what I care about is whether the rolling average is drifting the right way, not what any one week happened to score.
• Not chasing 300%. Once I’m clearing the floor consistently, I’d rather add a strength day than pile on junk miles.

The whole exercise is deliberately unglamorous: one honest percentage, benchmarked to the guideline that actually has outcome data behind it, with every tempting overclaim ruled out in advance. That’s the version of “tracking” I trust.

Not medical advice. This is a personal catalog of research I’m reading and habits I’m testing on myself. Nothing here diagnoses, treats, or prevents any disease, and it isn’t a substitute for a qualified clinician. Talk to your doctor before changing diet, fasting, exercise, or medication — especially with ADHD medication, alcohol, or a personal or family cancer history.

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