Mikko Puhakka
← All Hyrox updates

Hyrox training log

Weekly training and analysis

Week 34 (17–23 Aug) training based on Apple Health data – load versus plan, heart rate zones, pace, and recovery.

  • Hyrox
  • Training
  • Apple Health
  • Recovery
  • Analytics

Last week’s (Week 34, 17–23 Aug) training was pulled straight from Apple Health: six logged sessions, each at least 20 minutes. Here I go through what actually got done compared to the previous training plan, what heart rate says about the load, and what recovery looked like over the week.

Methodology note: a session’s overall average pace is a misleading metric any time a workout mixes hard and recovery phases — the average buries exactly the information that matters in interval training. So in this update, every session with distance data has had its sub-3-second-interval distance and heart rate data reviewed separately, so the hidden hard phases and recoveries stand apart instead of vanishing into one number.

This week’s sessions

Day Type Duration Distance Pace Avg / Max HR Calories
Mon 17 Aug Walk 42.5 min 2.85 km 14:53 min/km 102 / 127 192 kcal
Tue 18 Aug Functional strength training 58.6 min 141 / 171 530 kcal
Wed 19 Aug (no logged session ≥20 min)
Thu 20 Aug Run 39.6 min 5.34 km 7:25 min/km (avg)* 143 / 168 475 kcal
Fri 21 Aug Functional strength training 69.9 min 150 / 176 750 kcal
Sat 22 Aug Cycling 32.5 min 5.35 km 6:05 min/km 102 / 140 160 kcal
Sun 23 Aug Walk 65.0 min 6.26 km 10:23 min/km 122 / 143 489 kcal

Weekly total: 308 min (about 5 h 8 min) of exercise, 19.8 km covered in logged sessions, 2,596 kcal of active energy burned.

*Thursday’s “7:25 min/km” is the average pace across the whole 39.6-minute session — it includes both the hard interval reps and the recoveries between them. The real interval structure is broken down below in its own section.

Thursday’s interval session in detail: what the average pace hid

The whole session’s average pace (7:25 min/km) paints a picture of a steady, slow run. Unpacking the same data from its sub-3-second interval distance and heart rate samples reveals a clear four-phase interval structure — just two reps short of the planned 6×800m, but noticeably faster and harder than the average suggested:

Phase Duration Time range Distance Pace Avg HR
Warm-up 12.75 min 07:59:49–08:12:34 1,685 m 7:34 min/km 122
Rep 1 4.25 min 08:12:34–08:16:49 727 m 5:51 min/km 153
Recovery 1 2.25 min 08:16:49–08:19:04 196 m 11:29 min/km 143
Rep 2 4.25 min 08:19:04–08:23:19 711 m 5:59 min/km 155
Recovery 2 2.25 min 08:23:19–08:25:34 175 m 12:49 min/km 146
Rep 3 5.00 min 08:25:34–08:30:34 763 m 6:33 min/km 158
Recovery 3 1.75 min 08:30:34–08:32:19 144 m 12:10 min/km 142
Rep 4 4.50 min 08:32:19–08:36:49 746 m 6:02 min/km 160
Cool-down 2.75 min 08:36:49–08:39:34 196 m 14:03 min/km 151

The four reps add up to 2.95 km in 18.0 minutes — the real rep pace is therefore 6:07 min/km, not 7:25 min/km. That’s still a little slower than the planned 5:15–5:30 min/km target, but clearly closer to it than the flat average suggested. Heart rate climbed to 153–160 during the reps (max between 159–168, not shown in the table) and only dropped back to 142–146 during recoveries — meaning the recoveries were an easy jog, not a full stop, which keeps the whole session’s average heart rate (143) elevated even though the average pace looks slow.

For the week’s other distance-tracked sessions (Monday’s and Sunday’s walks, Saturday’s ride), the same review didn’t reveal a similar hidden structure — all three were steady, continuous efforts start to finish, so their table average pace describes the session correctly. Saturday’s ride had one short stop later on (about 7 min nearly stationary), but no repeating interval structure.

Load versus the plan

The previous update laid out week 34 like this: Mon strength+BBJ, Tue easy base run, Wed active recovery, Thu 6×800m interval session, Fri rest day, Sat Hyrox Combi, Sun long low-heart-rate combo. The outcome deviates from the plan in a few places:

  • Mon/Tue flipped: a walk landed on Monday and strength training on Tuesday — the reverse of the plan, but content-wise both planned stimuli still landed early in the week.
  • Wednesday went to plan: no logged session over 20 minutes, which matches an active-recovery day.
  • Thursday’s interval session happened, but as 4 reps instead of the planned 6: the closer review (above) reveals a warm-up, four reps of roughly 700–760 m at 5:51–6:33 min/km, and three recoveries between them. The rep pace (avg 6:07 min/km) still fell a bit short of the planned 5:15–5:30 min/km target, but was considerably harder than the whole session’s 7:25 min/km average suggested. Two reps were skipped, and the session was also shorter overall than the full 6×800m set.
  • Friday’s rest day became the heaviest strength session: 69.9 minutes, average heart rate 150 and max 176 — the week’s highest load landed on the planned rest day.
  • Saturday’s Hyrox Combi didn’t happen as planned: instead there was a light 32.5-minute bike ride at low heart rate (average 102), not the planned four-round combo.
  • Sunday’s long low-heart-rate session landed partially: a 65-minute walk at average heart rate 122 is the right type of stimulus, but shorter than the planned 75–90 minutes, and didn’t include the planned bike+SkiErg combo.

Overall picture: the week’s volume (about 5 h) came in clearly lighter than planned, and running-specific threshold work plus the Hyrox station simulation were missing entirely. Instead, the load unexpectedly concentrated on Friday’s strength session.

Heart rate zones

Resting heart rate varied between 61–72 bpm over the week, and the week’s logged sessions split clearly into two groups:

  • Low/recovery (avg HR ~100–122): Monday’s and Sunday’s walks, and Saturday’s ride. These landed well in the base-endurance zone.
  • Moderate/brisk (avg HR ~141–150, max 168–176): both strength sessions and Thursday’s run climbed clearly higher — closer to threshold than base endurance.

Thursday’s run’s whole-session average heart rate (143) makes more sense now: during the reps, heart rate climbed to 153–160 (peaks 159–168), and didn’t have time to drop below 142–146 during recoveries before the next rep. This is exactly the bottleneck already mentioned in the previous update: a 6:07 min/km rep pace already pushed heart rate close to threshold, so there’s still ground to cover between threshold-level running pace (target 5:15–5:30 min/km) and the current heart rate response.

Pace and duration

Four of the logged sessions had distance/pace data. Three of them (Monday’s and Sunday’s walks, Saturday’s ride) were steady efforts, and their table average pace (14:53, 10:23, and 6:05 min/km) describes the session as-is. Thursday’s run, on the other hand, is exactly where the average pace (7:25 min/km) is misleading, since it includes both the 6:07 min/km rep pace and the slow recoveries between them — the real rep pace is therefore much closer to the targeted Hyrox running pace (about 5:35 min/km) than the table figure suggests, though not there yet.

Recovery

  • Resting heart rate: stayed around 61–67 bpm from Monday through Saturday, but rose to 72 on Sunday — the same day as the week’s second low-heart-rate walk. The rise could reflect accumulated load (especially after Friday’s heavy strength session) or incomplete recovery.
  • HRV (SDNN): varied between 45.6–57.1 ms at the daily level. The lowest value landed on Friday (45.6 ms), the same day as the week’s heaviest session — a logical link between load and the recovery metric.
  • Sleep: varied from 5.4 hours (the night Sun→Mon) to 8.3 hours (the night Mon→Tue). The shortest night landed right before the week’s first session, and the longest night followed right after — the schedule evened itself out as the week went on.

In summary: the week came in lighter than planned overall, unexpectedly concentrated on Friday’s strength session, and didn’t include the planned Hyrox-specific station work. Thursday’s threshold interval session, on the other hand, turned out closer to plan in reality than the table’s average pace suggests at first glance — four reps at 6:07 min/km instead of the planned six. The recovery signals (elevated resting heart rate and the lowest HRV) consistently lined up with the heaviest training day, a good reminder that the program is worth adjusting to the load when needed, not just the calendar.

Follow the journey and training diary here at puhakka.org!