Day 31 of 300: Squash, the Forgotten Cardio
The day after crawling back to optimal, I played squash. Not because it was on the plan, but because a mate asked. Sometimes the best sessions happen when you’re not trying to have one.
I haven’t played squash in ages. It’s one of those sports that sits in the gap between “real exercise” and “messing around with friends.” Garmin knows better. Nearly two hours of court time, and the watch tracked every spike.
The session
- Duration: 1h 49m
- Calories: 581 kcal
- Heart Rate: 92 bpm (avg) / 155 bpm (max) / 52 bpm (min)
- Steps: 1,256
- Aerobic Training Effect: 1.8
- Anaerobic Training Effect: 2.3
- Training Effect Label: Anaerobic Capacity
- Training Load: 37.0
- Intensity Minutes: 39 moderate, 2 vigorous
- Body Battery Impact: -7
The average heart rate of 92 looks deceptively low. That’s the nature of squash. You sprint, lunge, swing, then stand still waiting for the next serve. The average gets dragged down by the rest periods between rallies. But the max of 155 tells the real story. During the hard rallies my heart rate was pushing into zone 4, then dropping back to zone 1 while we set up the next point. It’s interval training disguised as a game.
The training effect label came back as Anaerobic Capacity. That makes sense. Squash is short explosive bursts, not sustained effort. The aerobic effect was only 1.8, but the anaerobic hit 2.3. For context, yesterday’s base run scored 3.3 aerobic and barely registered anaerobically. Completely different stimulus, which is exactly what the body needs.
What 581 calories actually looks like
For comparison, yesterday’s 23-minute run burned 315 calories. Today’s squash session burned 581 in nearly two hours. On a per-minute basis, the run was more efficient (13.7 cal/min versus 5.3 cal/min). But I would never have run for 109 minutes. The squash session happened because it was fun. I was chasing a ball, not watching a timer.
That’s the argument for sport over structured exercise. You go longer because you don’t notice the time passing. The total calorie burn ends up higher even if the intensity per minute is lower. And 41 intensity minutes from a session I wasn’t counting as a workout is a solid contribution to the weekly target.
The body battery story
Body battery started the day at 75 and ended at 14. The session itself only cost 7 points, which is remarkably low for nearly two hours of activity. Yesterday’s shorter run cost 9. The explanation is the same as the heart rate average: lots of rest baked into the session. The body had time to partially recover between efforts rather than being under continuous load.
By the end of the day body battery sat at 16. Drained 62 points across the whole day against only 52 charged. Running a deficit, but not a dramatic one. The stress score stayed balanced at an average of 31, which means the session didn’t push my nervous system into overdrive.
Resting heart rate holding
Resting heart rate came in at 61 bpm, matching the 7-day average exactly. Yesterday I noted it had dropped to 58 during the run. Today’s 61 is the all-day measurement, which tends to sit slightly higher. The trend is still flat and healthy. No sign of the session causing any cardiac stress beyond the workout itself.
The case for variety
Thirty sessions in and this is the first time I’ve done something other than running. Looking at the training effect data, it’s clear why variety matters. Running builds the aerobic base. Squash builds anaerobic capacity. They stress different energy systems, different muscle groups, different movement patterns. Lateral movement on a squash court is nothing like forward motion on a treadmill.
The load ratio was at 1.0x as of yesterday. Adding 37 training load points from this session will nudge the acute load up slightly, but squash doesn’t stress the same systems as running, so the impact on running-specific fatigue should be minimal. It’s free fitness, essentially. Extra training stimulus without stacking more running volume onto legs that are still adapting.
What’s next
The plan hasn’t changed. Run tomorrow if readiness is above 40. Keep base effort. Sleep well. But I’m going to try to play squash regularly if I can. It burned more total calories than a run, gave the anaerobic system a stimulus it hasn’t had in weeks, and I actually enjoyed it. When the hardest part of a workout is remembering to bring a towel, you’ve found something worth repeating.
Day 31 of 300. First non-running session logged. The body is telling me it wants variety. Time to listen.
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