TRIATHLON TRAINING DADDY : Addicted to Triathlons? Me too. Follow along as I navigate faith, family, work and triathlon in every day life, share some tips and secrets, and help others fit it all in without missing out on life.

Thursday, February 8, 2018

Why does the distance on your watch differ from the treadmill!?

It's that time of year...

Everyone except the hard core are on the 'mills.  Dreadmill.  Devil's highway.  Whatever you want to call it, it's COLD as sh*t outside right now and people are on them.  Problem is, those number driven hard core metrics watchers are getting fed up with the inaccuracy of their recorded workout vs what the treadmill says they did.

I'm a HUGE fan of treadmills, used appropriately.  Long slow runs greater than 10 miles.. no thanks, but I'll do it if I have to.  But, this post isn't about converting you to the mill.

This is addressing the litany of questions, comments and frustrations I' get from athletes and readers about the accuracy of recorded workouts vs actual treadmill mileage.  I even get the issue myself.

There are TONS of reasons why what the treadmill says and what your watch says will vary from mild to wild.

  1. Not all treadmills are created equal.  I have a 7 year old Sole in my basement that I torture myself on.  How many times have I had it tuned up?  0.  Yep... I'm have no illusions about the complete inaccuracy of speed and distance on my machine.  I trained for an April marathon on that bad boy last year and in no way shape or form was it accurate.  I've learned to suck it up and go by feel and pay less attention to the metrics.
  2. Think about point 1 if you go from home, to the gym, to the community center, to a hotel... etc.  Different makes and models and who knows how well they are maintained.  Ask the desk attendant at your hotel when they last serviced the treadmills and be prepared for a deep stare into the oblivion.
  3.  For simplicity, I looked up the Fenix 5 user manual for indoor training.  Here's what they say.  "Indoor Activities - The fēnix device can be used for training indoors, such as running on an indoor track or using a stationary bike. GPS is turned off for indoor activities. When running or walking with GPS turned off, speed, distance, and cadence are calculated using the accelerometer in the device. The accelerometer is self-calibrating. The accuracy of the speed, distance, and cadence data improves after a few outdoor runs or walks using GPS. TIP: Holding the handrails of the treadmill reduces accuracy. You can use an optional foot pod to record pace, distance, and cadence."
  4. Another tip, if you mix up your runs with speed, cadence, AMRAP work, etc, expect this data to be even more dicey to calibrate accurately.
  5. If you get a solid calibration from GPS, again if you do speed, hills, or any other variance work on the treadmill, your watch will not know how to apply it and you might actually show a slower speed doing speed work.
  6. If you check your watch a lot, and stop swinging that arm, you will mix it up.
  7. If you swing your arms wildly while running, you could clock an inaccurate pace.
  8. This causes even more stress when people go to change the distance recorded by their device to be more accurate.  How many miles did you really run on the race pace workout with jogging and walking mixed in?
  9. Don't get confused on what products will fix this issue and give you accurate data.  Garmin has the HRM-Tri, HRM-Run and The Running Dynamics Pod.  READ CAREFULLY - they measure running DYNAMICS, none of which are pace and distance related.  You get some juicy tidbits about your running form, but none of it will fix the treadmill inaccuracy.
  10. The BEST bet for treadmill accuracy is the Foot Pod.  Garmin and a lot of others make them, and Garmin states "Unlike simple pedometers, this foot pod uses advanced MEMS inertial-sensor technology to analyze your movements and is responsive to stride-length changes to achieve 98 percent accuracy for speed and distance."  Read that?  Speed.  Cadance.  Distance.  It is your best bet for treadmill accuracy.

Thanks for reading!  Hope this helped. 

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