Thursday, November 5, 2009

MAF Test - 1st Timer - HR 145

6 miles - 46 minutes.

Did 4 miles at MAF - 7:25, 7:34, 7:39, 7:44. Average HR for the entire 4 miles was 144.
Did a mile w/u with the 2nd half of that mile getting my HR up in the mid 140's so I could start the first mile at a 145 HR. From what I understand this test will be a measuring stick to show improvement over the same course at the same HR. I'm curious to see not only if I go faster, but have a decrease in difference for each mile. Running at 145 was a little difficult, I was very comfortable at 146/147. When I'd try to get back down to 145 I seemed to go down to 142/143. This will definately take a little practice. Maybe, since it's comfortable, I should just run at 146/147. Or, maybe this is just defeating the purpose of not going above 145...


  1. Good stuff. Faster than me at that HR.

  2. Unless you've had a blood test to confirm, its all an arbitrary guess anyways. I wouldn't stress about any particular number...just the difference over time. My two cents.

  3. The MAF test is based solely on metabolism/ fuel preference. A short warm-up will probably yield less accurate results. You have to give your body time to start processing fat. The longer the test the better also as it can give you an indication where your "endurance" (loose term) is. A 3 mile warm-up is almost mandatory to get your body in to the correct metabolic state and the first mile should be slow enough to not bring your HR up to even MAF. For you I would say to run the first mile in ~8:30-9:00 pace, then the second mile in ~8:00. Then get to MAF for the 3rd mile and hold it. Then go straight in to the test. For you also, a 10-12 mile test may be more beneficial to see the drop off in pace. At a certain point you'll see severe pace deflection where you run maybe 30"+ slower for a mile at the same HR. This could be where you lose economy from low fuel or fatigue (dehydration is also going to play a major role here as HR is affected most by fluid levels in your blood).
    And Brett is right that MAF is quite arbitrary and I only use it for athletes who don't know their AeT/ LT(FT). It is good though for periodic testing to monitor improvement. And you don't want to hear this, but I would have you cap your HR at 145 MAX just to be safe. If you were training for a fast marathon then going to 150 would be more appropriate. When I start training for Leadville I'll spend at least 2 months resetting my metabolic economy so that I get strong and fast at HR 135-145. By doing this you teach your body to prefer fat even at faster paces. For an ultra (IMO) this is rule #1. And remember that MAF was born with the Ironman, a race of over 8 hours, in mind.
    Just my 3 cents (inflation).

  4. Good stuff.

    FWIW ... I have started calling it "fixed HR" training ... the concepts above are the same but you may not "exactly" be at your "maximum" aerobic function at 139, but if you test at that all the time - you want to see your paces getting faster.

  5. I couldn't agree more GZ. I tried to get away from the the term MAF but couldn't find anything better besides 'low HR'... "Fixed HR" it is!!

  6. Thanks guys, that's alot of good info. I thought this was going to be something simple that I could squeeze in mid week once in a while. This is something that I could actually do on a Sat, before I do a long run on Sun, for some great training.
    I can tell from today that I have gained alot from the long, slow stuff I've been doing on the weekends. It's always good to be able to see the results to re-enforce the good training.