How Much Does an Age-Grouper Really Train?
Anyone who has asked a coach how much they should train has heard some version of “it depends.” A weekly plan for a half distance should look different from one for an Ironman, that much is known. What has been missing is a concrete benchmark for how much the average age-grouper who actually finishes the race trains in a week. Until now. In May 2026, TrainingPeaks published a rundown on its blog of an independent scientific study in the peer-reviewed journal Frontiers in Sports and Active Living, giving the first real picture of that answer.
What was studied, and how
This was not a survey. It was objective session data exported from TrainingPeaks over a six-month period. Every participant had duration, distance, heart rate, Training Stress Score (TSS) and power zones logged. In total: 2,177 weeks of training from 95 age-groupers across 25 countries, 34,731 individual sessions.
The sample is small in athlete count (95) but enormous in logged sessions. The data is objective, not raw Strava pulls where one athlete’s GPS catches a signal and another’s does not. The study was carried out by researchers at Deakin University in Australia and published in a peer-reviewed journal.
Athletes were split into two groups:
- Short-course: sprint, Olympic and middle distance, up to and including 70.3.
- Long-course: full Ironman (140.6).
Numbers worth pinning above your desk
Weekly averages, taken across the full season:
| Group | Minutes/week | Kilometres/week | TSS/week |
|---|---|---|---|
| Long-course (Ironman) | 615 min (10h15) | 171 km | 574 TSS |
| Short-course (up to 70.3) | 507 min (8h27) | 118 km | 452 TSS |
The claim that finishing an Ironman requires 15 hours a week of training still circulates in age-group circles, and these numbers are a reality check. The average is 10h15 for the full distance. Not 15, not 20. Ten, on average.
For a half-Ironman, the short-course average is 8h27 a week. Also less than popular plans suggest.
The second finding: training phase outranks age or sex
The most interesting observation in the study: age and sex were weaker predictors of training load than the phase of the season. In other words, whether an athlete is 30 or 45, a woman or a man, the strongest influence on their weekly load is which phase of the season they are in.
In the specific phase, the weeks closest to race day, TSS load runs about 21% higher than the general phase. In the taper/race/post-race phase it drops about 14% below the general phase. In the off-season it hits its low point: the study puts it around 340 min/week, roughly 38% below the general phase.
That sounds obvious, but it has real consequences:
Generic “12-week to Ironman” plans deserve suspicion. If a plan does not vary load between base, specific and taper phases, discard it.
Comparing yourself with others on Strava only makes sense within the same phase. If a training partner logged 620 to 650 TSS in a week, check whether they are in the specific phase while you are just entering base.
“Only 8 hours a week, so I won’t finish?” is the wrong question. Eight hours in the specific phase with well-distributed TSS can be more effective than 12 hours of chaotic hard work.
What this means for the everyday age-grouper
For an amateur working a 40+ hour week, this is good news:
1. Your goals are more realistic than you think. Giving 8 to 10 hours a week puts an athlete in the international average for age-groupers finishing a half-Ironman. Fifteen hours a week is not required to finish a 70.3.
2. TSS counts, not time. The 452 TSS/week short-course average works out to roughly 65 TSS a day. That could be an easy 90-minute ride (about 50 to 60 TSS) or a 60-minute threshold run (80 TSS). What matters is that the weekly total adds up.
3. Periodisation beats volume. The same training time, spread through a 3:1 progression (three weeks building, one week recovering) with distinct phases, produces dramatically better results than training 8 flat hours a week all year with no variation.
4. Compare against the average, not the elite. A pro trains 25 to 30 hours a week at 1,200+ TSS; that is not the right benchmark. The benchmark is 615 minutes and 574 TSS for an Ironman.
What not to do with this data
Two interpretive traps worth watching for:
Trap 1: “If the average is 10 hours, 10 hours is enough for me.” That figure is averaged across the whole season and the whole sample. What counts as “enough” depends on the finishing time being chased. Finishing an Ironman in 14 hours is a different task from qualifying for Kona.
Trap 2: “If TSS is 574, every week should be 574.” No. That is a seasonal average across different phases: base weeks run around 400, the specific phase 700 to 750, taper below 500. Week-to-week fluctuation is correct and expected.
The verdict
The first study of this scale shows that finishing an Ironman as an age-grouper does not require living like a monk. It requires consistency, periodisation and a defined TSS load, distributed sensibly through the season. The average is 615 minutes a week. Not 1,000.