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Treadmill running

I did my long run on a treadmill today, 2 hr, 14.2miles, 8:28pace. The alternative was running city streets at 430am - not for me.

Very clearly, the run on treadmill felt easier. I would like to believe my fitness is improving, but I suspect the treadmill is just easier despite increasing my z2/z3 paces and adding 1% incline. HR stayed at about 138-145. Last week during the long run on the street, my ave HR was around 160 at slower paces and definitely hurt more.

I suppose this is due to the fact that the belt is propelling you? My legs are hitting the belt, so I don't really understand it. 

The biggest advantage is convenience, by a long mile. I know Potts does his training in a cave, but curious how to equalize my treadmill experience with an outdoor run.

DS

Comments

  • I do one run a week on the TM simply because it is so damn hot in Texas I give myself a break on that day.  It is easier because it is a controlled environment.  I have a fan blowing, TM @1% to compensate for the belt running and about 76 degrees.  I get in a great quality workout controlling those variables and it also helps me focus better on cadence.  Once a week, in my opinion is value added given I am running 6 days during the week, however, I would not substitute all my runs with TM runs and, for that reason, I do my other 5 runs a week outside.

    Keep up the good work!

    SS

  • Living in Dallas, like Shaughn, I frequently do long runs on the dreadmill. For some reason, I'm much more able and willing to spend 2+ hours on the mill than that same amount of time on the stationary trainer.

    I use 1.5% at the gym treadmill, with the a/c and/or fan blowing on me. The gym treadmill is nice because it forces you to restart after each hour, which is good for a bathroom break for me. And towels, LOTS of towels! Sweatfest!

    I find after a lot of treadmill running that my hip flexors are tender, so just be careful to not do a hard bike session for a few days after a long mill session. my $.02.
  • I know it may not be the smartest idea posting stuff as a noob, but TM running is something I know about: I do it about two to three times a week (not because I choose to, because I have to - child care at the Y is one of the reasons I'm in shape!).

    Because terrain/speed is controlled, you can clearly see your body adaptations. Great tool for fitness testing. But yes, don't replace your outdoor runs with TM work: You will find that if you do you will need a few weeks to re-adapt your feet and ankles to the rigors of the road. The TM surface is much more forgiving than asphalt.

    The reason you need incline on a treadmill in order to match the resistive force due to wind resistance you experience on the road. When you leap off one leg to the other, the air friction due to your speed actually pushes back on you. Very little, but it's there. TMs have no wind resistance. So you compensate for the wind resistance on a TM by introducing resistance due to gravity: the incline forces you to fall back a little just like the wind outdoors.

    You will find that TMs are extremely variable in accuracy: Speed and incline can differ radically between machines. I actually calibrate the ones I use against my heart rate like this: I find a stretch of flat road (I use the Manhattan Beach boardwalk in LA) and do a 5k tempo run. You may not even need a full 5k to do this, probably about 2 miles will suffice. I try to keep my pace as consistent as possible. At the end I note my average pace (7:30, say) and MAX heart rate (if done right this will be at the very end of your run). Then, a day or two later I set the treadmill to the pace I ran (7:30) and a certain incline, say 2%. If I reach my max heart rate earlier than 5k, it means 2% was too much, if later, then it was not enough. I repeat the TM sessions (after a few days rest) until I get it to match, and voila! You know what incline you need to match flat ground.

    For me I have about three machines at my Y where I know how to set their incline. One is 1.5%, one is 2%, and the other is 3%!!!! Variable.

    I also use a footpod on the TM to measure my speed, although when the pod doesn't match the TM, I'm kind of at a loss to know which to go with!

    Brian.

  • My treadmill runs felt hard, so I measured the speed on my treadmill and was really surprised to find out how inaccurate the speed settings were... treadmill was running 18% faster than indicated.



    It is pretty easy to do - I just put a white spot (correction fluid) on the belt, measured the length of the belt and then timed how long it too to make 10 revolutions. I made several different measurements (used the average) at several different speeds. I plugged it into excel and calculated the variance. All my speed settings were off by the same factor.



    Oh - I also did the checks while running, in case me running on the belt changed the speed.



    Now I have a little conversion chart:

    If I want… Set speed to…

    5.0 mph 4.1 mph

    6.0 mph 4.9 mph 

    7.0 mph 5.7 mph 

    8.0 mph 6.5 mph 

    9.0 mph 7.4 mph

  • Doug,

    Not much to add but also consider your elevation outside.  If you just leave the treadmill at 1% you don't hit any hills.  I typically run inside for a lot of the OS and leave it at 1-2% but you could add in some elevation over the long run.

  • Great info. Thanks all. The rain has arrived, so expect to see the mill more and more often now. 

  • I'm re-visiting this convo if it's ok with you guys.

    Did my 5k test on the TM yesterday. I do most of my speed work on the mill, and my longer runs outside when temps allow. My TM definitely runs way SLOW (always at a 10min pace per mile no matter where you set it) so I only gage my speed with my 920 and footpod. I had the 910 last season and would calibrate it each run. Now I guess the 920 does it for you. I was able to hammer out a 21:06 with a 2% incline yesterday, and felt awesome.... however, I'm skeptical of how accurate it is.

    Part of me wants to just dial in the new zones and give it a shot, while the other part of me doesn't want to take credit for 6:45 mile splits...

    Anyone had similar scenarios with their TM runs? Anyone tried to measure the accuracy of the 920?
  • Emily, seems to me that the TM time is only of value for when you are doing workouts on that same treadmill, at (close to) the same speed. In other words, you have a VDOT for that treadmill, and should feel comfortable using it when you do intervals on that specific machine. But don't presume it is useful for training or racing outdoors. When that time comes, just go run a local 5K race and get a real outdoors VODT.

  • And that's why you're a WSM. Thank you, Al! Great advice.
  • Emily - When I run on a treadmill, I wear my Garmin 220. Like the 920, it uses an accelerometer to gauge your pace based on the swing of your arms. My understanding is that it calibrates the accelerometer outdoors, then uses that calibration when you turn the GPS off and run indoors. Have you done much outdoor running with the 920 before getting on the treadmill with it?

    Lately I've found the Garmin accelerometer to be wildly inaccurate indoors. I can be running at an 8:40 pace (per the treadmill - I use several different treadmills) and the Garmin says I'm at a 10 or 10:30 pace. I can tell based on RPE that the pace is much closer to the 8:40 than 10+. Accordingly, I typically use the TM to gauge my pace and use the Garmin to record my heartrate. Is the TM perfectly accurate? Probably not, but it seems a lot closer than the Garmin.

    I have never used a footpod with a Garmin, but according to the authority (DCRainmaker), the foot pod is the best way to get pace indoors using a Garmin; it is far and away more accurate than the accelerometer.
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