STRYD Tests: Varying Terrains & Speeds


STRYD – Running Power

More tests today. Here are some results and inferences.

Test 1: Flat, constant speed, Varying surfaces

  • Tarmac: 3:59/km, 260w
  • Firm track: 3:53/km, 260w
  • Grass, mildly soft: 3:59/km, 264w

My Inferences: Surface appears not to be taken into account.

Test 2: How does power increase with pace? Exactly the same external conditions for each interval.

  • 3:20/km, 269w
  • 3:41/km, 263w
  • 3:45/km, 258w
  • 4:09/km, 256w
  • 4:36/km, 239w
  • 4:42/km, 242w (?)
STRYD: Power vs Pace

STRYD: Power vs Pace

My Inferences: Looks fairly linear to me. [I had the pleasure of Dr Andrew Coggan confirming to me on a forum that this should be expected in normal power ranges as VO2 increases linearly with speed/pace]. I would not have thought that, so it’s always good to learn.

Test 3: Extended Uphill – same gradient (relatively gentle but enough to slow us all down) and wind, different surface

  • TARMAC – 4:24/km, 280w
  • SOFT, BUMPY GRASS – 4:25/km, 270w

My Inferences: Looks wrong to me. Possible some element of my technique may have changed??

Test 4: Medium Downhill (relatively gentle), sheltered, different surfaces.

  • TARMAC – 3:18/km, 275w
  • SOFT, BUMPY GRASS – 3:23/km, 281w

My Inferences: Inconclusive. Initially I thought that this looks wrong but possibly correct. I would have expected much more power required as ground was soft. Yet I ran slightly slower and required 6w more on the bumpy grass. BUT had I ran at 3:18/km/h on the bumpy grass then maybe the watts would have been a fair bit more +10w? That would then look more sensible I guess.





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Race LeaderJavier De Pedro Ormeño Recent comment authors
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Javier De Pedro Ormeño


How much lasted the test stimulus?

Good article!!

Race Leader

too short to be scientific.
I spent over 3 hours testing stryd with my tests and then also add on general (and ongoing) usage. If you mean the intervals they were for at least 2 minutes, so enough to adjust pace to a target average.