Treadmills and speed work
I tried running one of the FIRST speed workouts on the treadmill at the Camp Hill LA Fitness tonight. This was a bit of an experiment since I haven’t ran anything faster than 5k pace in quite a while (months?). The workout called for 12 x 400m @ (10k pace – 55/60 seconds per mile) with 90 seconds rest interval. I’m currently using an estimated 10k time of 42 minutes for my FIRST calculations since my 5k times have been just under 20 minutes lately. A 42 min 10k pace is 6:45, so subtracting 60 seconds makes the target pace for the 400m interval a 5:50 to 5:45 minutes/mile pace.
I had also recently purchased a Garmin footpod which attaches to your shoe and uses an accelerometer to gauge how fast you are running and transmits this to your Forerunner. I really liked the idea being able to capture treadmill workout data since previously when running indoors I can only capture my heart rate and I have to remember what speed I had set on the treadmill during various parts of the workout.
I started with a warmup for .8 miles on the treadmill and the footpod seemed to be generally accurate to within 2-5% for speeds from 12 minute miles down to 7 minute miles when I was eyeballing it. At the end of the warmup the treadmill had me listed as having covered .81 miles and the footpod told my Forerunner I had completed .80, so it was almost dead-on. When I tried some faster speeds briefly (sub 6 minute mile) the accuracy started decreasing, but you can also calibrate a footpod to help increase the accuracy which I have not done yet. If anyone is considering getting a footpod, check amazon.com for prices, I found it for about half of what the Garmin online store listed it at.
Now that my warmup was completed, I started a new workout on the treadmill using the interval mode. This feature lets you program in two running speeds, and by pushing the “interval” button, it will automatically switch between them. I programmed in 4.5 MPH for the jog speed and 10.4 MPH for the interval speed. I jogged for a little bit and then pressed the interval button. It took a handful (4-6?) of seconds to ramp the speed up from 4.5 MPH to 10.4 MPH. The first few intervals weren’t too bad, but the time it took the treadmill to ramp up and down in speed as the interval was starting or ending made some of the calculations a bit fuzzy. I was trying to figure out how many seconds in advance to hit the interval button, but after a little while I gave up on it and just accepted it wouldn’t be an extremely precise workout. For workouts where the intervals are longer, the ramp up/down time is less of an issue. I also realized during the workout that I should have made my jogging pace something like a 2 MPH walk in order to have better recovery during the 90 seconds rest intervals. I started doing this after the 7th or 8th interval, which helped get my heart rate back down quicker, but the slower starting pace increased how long the ramp up time took. I ended up calling an end to the speed workout after completing 10 intervals since my legs were feeling pretty beat even though I was still recovering aerobically. When you run intervals outside, as you fatigue your pace naturally drops. On the treadmill, you end up running at the set pace (or you fall off). I’ve read that it is easier to pull a muscle during workouts on a treadmill when you are pushing it since your body’s natural mechanism to slow down isn’t available as you fatigue.
Overall I had a pretty good workout. I think when running longer intervals the whole treadmill ramp up/down time won’t be significant and the footpod seems to work pretty well. I checked the workout data from Garmin Training Center, and it had my max speed for intervals at anywhere from 10.4 to 10.6 MPH which is really close to what I had the treadmill set to (and certainly the treadmill may not be perfect either). I’m going to calibrate the footpod this weekend on a track and see if the accuracy improves.
November 29th, 2007 at 2:20 am
More power to you… I have trouble even looking at a treadmill. That last bit about pulling a muscle on the treadmill makes a lot of sense. Your body is just “surviving” (ie not falling off). I’m sure that I will be introducing myself to the treadmill at some point this winter. I’m not looking forward to it.
November 29th, 2007 at 8:57 pm
Seems like you made the most out of the treadmill workout. Good work. It’s going to be very interesting to watch you on the FIRST program in a North Eastern winter. That is not meant as a snide remark either. I would do it as well, I just think winter will throw you curveballs and I am interested to see how you get through it all. Good luck.
I am going to join LA Fitness next week (as long as my hip can take the bike over there). So we’ll have to meet up at Camp Hill after I do.
November 30th, 2007 at 2:10 am
Nathan – see if you can find a free pass to LA Fitness. I had a two week pass that Mark Rebuck used when he went to check it out, and that increased his bargaining power a little bit. The sales guy said “if you sign up now instead of using the free pass I’ll drop $50 off the initiation fee”.