Week 38: training and analysis — back to Hyrox rhythm

Week 38 (14–20 Sep) was, as planned, a return to a normal Hyrox rhythm after race week: an easy start, a controlled interval session, and a full-scale Hyrox station simulation on Saturday.

This week’s sessions

Day	Type	Duration	Distance	Pace	Avg / Max HR	Calories
Mon 14 Sep	Running (morning run)	44.8 min	7.01 km	6:23 min/km	142 / 154	560 kcal
Tue 15 Sep	Combo: Rowing + Gym + Running + Walking	60.3 min	1.55 km*	–	133 / 152	524 kcal
Wed 16 Sep	Three parts: Cycling + Gym/Walking + Cycling	48.0 min	8.99 km*†	–	104–107	365 kcal
Thu 17 Sep	Three parts: Cycling/Gym + Cycling + Walking/Running (intervals)	126.8 min	17.70 km*†	–	113–146	1,251 kcal
Fri 18 Sep	(rest day, no session logged)
Sat 19 Sep	Hyrox Combi (3 rounds)	78.2 min‡	2.34 km*‡	–	149 / 169	728 kcal
Sun 20 Sep	Long low-heart-rate combo: Cycling + Walking	162.4 min	18.56 km*	–	103–109	849 kcal

Weekly total: 540.0 min (9 h 00 min) of exercise, 60.32 km covered, 4,407 kcal of active energy burned — clearly more volume than the previous easy recovery week’s start intended, concentrated in Saturday’s and Sunday’s long sessions.

* A combo/multi-part day’s distance is the sum of its parts. † Includes both a morning and an evening session with more than a 10-minute gap between them, so they weren’t merged into one session. ‡ The Hyrox Combi’s duration and distance cover only the segments Apple Health logged as their own Running and Cross Training sessions — most of the station content produces no distance or rep data at all, see below.

Tuesday’s strength session: three rounds

Tuesday’s 36.1-minute Gym segment (average heart rate 133, max 152) was done as three rounds — the data doesn’t separate the rounds from each other, but the steady average heart rate across the whole segment fits with a round-based, even-tempo strength session. Before and after the gym there was a short rowing (7.8 min) and running warm-up (7.2 min) plus a closing walk (6 min) — the whole morning was thus one continuous, four-part 60.3-minute whole.

Wednesday: the cap was mostly held

The plan had marked a clear upper limit for Wednesday: “30–40 min easy, no more” — precisely because of last week’s 127.7-minute overshoot. The outcome was three short parts (cycling 9.8 min, gym+walking 28.4 min, cycling 9.8 min), totaling 48.0 minutes — a bit over the cap, but radically better controlled than last week. Heart rate stayed low throughout (104–107).

Thursday’s intervals in detail: the middle rep went to pieces

The evening running session (18:55–20:09, total duration 73 min including the warm-up and cool-down walks) was the plan’s 5×800 m interval session. Unlike previous weeks’ track-style reps, this was run on the street with no clear stops between reps, so the GPS data doesn’t split as cleanly into discrete 800-metre blocks — but broken into 5-minute windows, exactly the story the legs told shows up directly in the data:

Window	Distance	Pace	Avg HR	Max HR
19:10–19:15 (start)	788 m	6:21 min/km	139	146
19:15–19:20	700 m	7:09 min/km	143	149
19:20–19:25	915 m	5:28 min/km	159	163
19:25–19:30	885 m	5:39 min/km	159	168
19:30–19:35	849 m	5:53 min/km	162	167
19:35–19:40	881 m	5:41 min/km	163	166
19:40–19:45 (dip)	780 m	6:24 min/km	161	167
19:45–19:50	855 m	5:51 min/km	160	164
19:50–19:55	824 m	6:04 min/km	160	165
19:55–20:00	776 m	6:26 min/km	160	166
20:00–20:04 (finish)	595 m	6:57 min/km	153	157

After the opening two windows (6:21 and 7:09 min/km — warm-up), pace clearly climbed for three consecutive windows to 5:28–5:53 min/km, heart rate at 159–163. Then comes exactly the dip: 19:40–19:45 pace drops to 6:24 min/km while heart rate stays high (161) — the classic signature of a rep that “went to pieces”: output couldn’t hold the pace even though heart rate didn’t drop. After that, pace never returned to the earlier level (5:51–6:26 min/km for the rest of the run) — the data directly confirms what the legs felt: the load was still there, and the pace had to ease off toward the end.

Saturday’s Hyrox Combi: three full rounds, data vs. plan

Saturday’s round was full-scale: 800 m run on the treadmill at a steady 5:30 min/km + 500 m row + 500 m SkiErg + 40 m Sandbag Lunges (20 kg) + 40 m sled push (153 kg) + Farmer’s Carry 2×24 kg, 140 m, three rounds. Apple Health logged each round’s run and row as their own separate sessions:

Round	Running (as logged by Apple Health)	Rowing	Other station content (Functional Strength Training)
1	5.1 min, 800 m (logged pace 6:22 min/km), avg HR 138	3.4 min, avg HR 144	14.8 min, avg HR 146, max 167
2	5.0 min, 770 m (logged pace 6:29 min/km), avg HR 151	2.6 min, avg HR 155	14.5 min, avg HR 152, max 169
3	5.0 min, 720 m (logged pace 6:56 min/km), avg HR 153	2.8 min, avg HR 153	18.0 min, avg HR 148, max 167

Correction: the treadmill belt ran at the same, manually set 5:30 min/km on all three rounds — there shouldn’t be any real difference between the runs. The round-by-round slowdown Apple Health logged (6:22 → 6:29 → 6:56 min/km) is a data artifact, not a real effect: an indoor treadmill’s distance is estimated from the wrist’s motion sensor, not from the belt or GPS, and that estimate drifts easily on short, start/stop-heavy 800-metre efforts. This is a different failure mode than the “distance missing entirely” problem seen in previous weeks — this time distance gets logged, just incorrectly. Rowing, SkiErg, Sandbag Lunges, sled push, and Farmer’s Carry still don’t produce their own distance or rep data in Apple Health — the same recurring issue as previous weeks — so they all show up in the data as a single “Functional Strength Training” block per round. Round 3’s block (18.0 min) is clearly longer than the first two (14.8 and 14.5 min) — this one, on the other hand, could well be a real, fatigue-driven slowdown at the stations, since they lack a treadmill-style pacer to hold them steady.

Sunday’s long low-heart-rate combo

Sunday consisted of three parts: two rides (46.8 min combined, 8.95 km) and a long walk (115.6 min, 9.61 km) — 162.4 minutes of movement in total. That’s clearly more than the planned 75–100 minutes, but heart rate stayed unusually low the whole time (103–109 all day) — intensity was exactly right, even though total duration ran long.

Load versus the plan

• Monday’s morning run went to plan: 44.8 min and 6:23 min/km is close to the plan’s 45 min / 6:00 min/km target, a touch easier than planned.
• Tuesday’s strength session went to plan, done as three rounds as intended.
• Wednesday was mostly controlled, though slightly over the cap (30–40 min) — a dramatic improvement over last week.
• Thursday’s interval session happened, but not at the target pace: the plan’s 5:30–5:45 min/km target was never hit, even at its best windows (5:28–5:53 min/km came closest) — and the mid-run dip plus the late-run slowdown show up directly in the data, exactly matching how it felt.
• Friday stayed a rest day, exactly to plan.
• Saturday’s Hyrox Combi returned to full scale — three rounds with the complete station content, as planned.
• Sunday exceeded the planned duration, but kept intensity at exactly the right, low level.

Heart rate zones and recovery

• Resting heart rate varied between 61–70 bpm, rising slightly toward the end of the week (61 Wed–Thu, 68–70 Fri–Sun).
• HRV (SDNN) swung widely: 38.4 ms (Monday, following the end of last week) → 46.3 → 60.4 (Wed) → 44.1 (Thu) → 54.9 (Fri) → 50.0 (Sat) → 75.1 (Sun). Sunday’s unusually high value (75.1 ms) lands right on the recovery day after the hard Hyrox Combi session — a good sign that Wednesday’s capped load and Friday’s rest day built a foundation the body could recover quickly from after Saturday’s effort.

Heart rate and max heart rate, visually

Dark bar = average heart rate relative to a 90–180 bpm scale, vertical line = max heart rate.

In summary: week 38 returned well to Hyrox rhythm — the Combi returned to full scale and Wednesday’s load stayed mostly under control. Thursday’s interval session missed the target pace, but the data confirmed exactly what running it felt like: the middle rep went to pieces, and the legs forced a slower pace toward the end. This gets factored into next week’s interval dosing.

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