After the latest Garmin beta, one new data field caught my attention and got me to thinking. MpB, or Meters per Beat, is said to be similar to MPG in a car. It measures the efficiency of an athlete. If an athlete runs 200m in 1 minute and averages a HR or 125bpm then they have a 1.60MpB. Of course this is a very short example, but this is something that can be tracked throughout a workout, field test or race to see the variance in MpB throughout the effort. Take that same athlete after 4 weeks of training and they do 200m in 1 minute but this time averages on 115bpm. Now they have a 1.73MpB. Although they did not run any faster (which many would chalk up as a non-improvement) they were more efficient at that pace. On the flip side, consider they ran for 1 minute at the original 125bpm but this time when 220m they would have a 1.76MpB.
Now this is obviously going to be unique from athlete to athlete. Some runners are diesels running race pace at only 140bpm while others are side-by-side with the diesel but is running at 170bpm with the same metabolic cost. So, I guess what I’m trying to see if you guys think this is a viable way to measure efficiency and/or fitness improvements.
After the latest Garmin beta, one new data field caught my attention and got me to thinking. MpB, or Meters per Beat, is said to be similar to MPG in a car. It measures the efficiency of an athlete. If an athlete runs 200m in 1 minute and averages a HR or 125bpm then they have a 1.60MpB. Of course this is a very short example, but this is something that can be tracked throughout a workout, field test or race to see the variance in MpB throughout the effort. Take that same athlete after 4 weeks of training and they do 200m in 1 minute but this time averages on 115bpm. Now they have a 1.73MpB. Although they did not run any faster (which many would chalk up as a non-improvement) they were more efficient at that pace. On the flip side, consider they ran for 1 minute at the original 125bpm but this time when 220m they would have a 1.76MpB.
Now this is obviously going to be unique from athlete to athlete. Some runners are diesels running race pace at only 140bpm while others are side-by-side with the diesel but is running at 170bpm with the same metabolic cost. So, I guess what I’m trying to see if you guys think this is a viable way to measure efficiency and/or fitness improvements.
Interesting. I wonder how useful it really is though. I have noticed in the past when I do treadmill runs especially that over time my HR average is lower for runs at the same speed/distance. While yes that is a metric of efficiency I don’t quite know what to do with those data other than say “hmm yea I am more efficient”
In the field of exercise physiology - indeed, in science in general - efficiency is defined as energy out/energy in x 100%.
Knowing how far you travel (or how much power you produce) with each heartbeat may, or may not, be useful in evaluating/guiding one’s training, but one thing is certain: it ain’t a measure of efficiency.
Over a long period of time you’ll see some trends. I think I remember seeing that Andy Coggan, who has already commeted, tracked joules per beat or something similar for a while and found it increased with training.
Day to day, it might work if you control the general effort level, heat, indoors vs outdoors etc. But assuming you don’t control those things, it will be noisy from day to day.
I don’t see a way in which it would guide your training day to do or week, unless there is something I am missing as yet.
There are several metrics like this around that the devices can now track but we as a community of scientists coaches and athletes don’t yet know what to do with. It’s only really after the metrics are out and used by a few thousand people that we will start to know if they have a practical use for athletes.
Yeah, I can see how it would be very different day-to-day and with power meters and HR monitors their are easier ways to measure these gains in a shorter time frame (which is what we all want anyway right? results yesterday!) Here is the description on the Garmin website.
Description
A way to measure efficiency in a car is miles per gallon or kilometer per liter. A corresponding measure for measuring efficiency of the body’s engine is Meter per pulse Beat.
Running 15km/hour at a pulse of 150 beats per minute gives a Meter per Beat of 1,66. Biking at 30km/hour at 150 beats per minute gives 3,33 Meter per Beat.
An athlete trains to get better. That means, at the same pulse racing at a higher speed! The key is to improve the Meter per Beat measure.
This datafield will allow you to view Meter per Beat information for your current activity. Either in graph format (building a distribution over the activities time) or by viewing the actual and average value as the workout progresses.
Benefits with Meter per Beat:
Allows to see improvement in one activity over time (increase in Meter per Beat - your fitness curve!).
Allows to compare your engine in various type of activities (how much more efficient are you on a bike compared to walking or running?)
Cheaper than measures requiring power meters. Power is harder to measure in different activities (most easy on a bike or machine).
Note:
Noice from different temperature, weather, routes will affect the meter per beat. Even the length of the workout. However, doing a measurement trail for your activity once per month will allow you to track the improvement of your fitness!
Give it a try and tell me what you think!
Description:
An athlete trains to get better. That means, at the same pulse racing at a higher speed! The key is to improve the Meter per Beat measure.
Here is your big error in all of this. The important thing is that an athlete goes a higher speed, who cares if they are now going this higher speed at the same pulse or if the pulse is higher or if the pulse is lower.
Let us say that I cycle I has hard as I can for an hour. I average 200 watts and 150bpm. I train for awhile and do the test again. Which result would be better 210 watts at 150 bpm or 215 watts at 155bpm or 220 watts at 170bpm? The correct answer is the 220 watts case, because it is higher.