Cycling for Weight loss: What every cyclist ought to know about power meters.
To Power or not to Power, that is the question
By Clint Latham – Get Free updates of new posts here
Let me start by saying this. Power meters are awesome and in fact they are one of the best cycling performance tools to date. If you are serious about racing then you need a power meter. Without one you’ll be left in the dust. Power meters give us a way to measure actual work load. How many watts are you putting into the pedals. Then through a series of test we determine our LT or Lactate Threshold. This benchmark allows us to fine tune our training and then measure our performance gains with a re-testing of LT.
The Downside of Power
Power meters are still expensive. You’re looking to spend at a min $500 for the meter and then assuming you have a bike computer that is compatible. Another couple hundred bucks for a new bike computer. Then comes the installation. If you’re not comfortable tearing your bike a part you will have to have a mechanic install and calibrate your power meter. If you’re like me and have multiple bikes, well then you need to repeat this procedure for your road, mountain and fat bikes. Get my point!
Our goal is just to get you back on the bike. We’re not looking to race, we want to shed some weight and have fun. Once you hit your goal and you start thinking about a charity race or joining the local criterium series. Then it might be time to think about getting a power meter. Until then we will take advantage of our $35 heart monitor, that we can use on any bike we ride.
The Downside of Heart Rate only
The heart rate monitor does not give us a complete picture of the body’s workload. Our heart rate can also be affected by outside factors such as heat, diet, stress, lack of sleep etc. Finding your true maximum heart rate is very challenging and in some cases might need to be done in the presence of a medical professional. I have also heard a number of elite level coach’s indicate that as their athletes reach a peak level of fitness, their maximum heart rates drop. This could be because the athlete is in such good physical condition that its almost impossible for them to put enough stress on the body to raise the HR to it’s ceiling. Heart rate alone also tells us nothing about your performance. We have to couple it with RPE or Rate of Perceived Exertion. If you couple heart rate and power together then you have a very powerful tool.
Why you DON’T need a power meter
I know you’re asking yourself right now, you just told me how great power is and how many limitations heart rate has by itself. So don’t I need a power meter?
If your goal is to lose weight and have fun on the bike then the answer is, NO. Knowing how hard the heart is working is very important information and allows you to make decisions about your workout progress. Especially when you couple this with RPE. Which does not require any additional equipment. When you are Riding to 75, at the end of each work out make notes of time, distance, average heart rate and RPE. Rate RPE on a scale of 1 (being easiest) to 10 (being the hardest). Over time you will start to get a better understanding of how your body is reacting to your training and building fitness. You will start to learn if you need to increase your Ride to 75 heart rate or if you need to bring it back a little bit. For example. If you are hitting your Ride to 75 heart rate and your RPE is in the 8-10 range for almost every ride. Then it might be time to taylor it back as your work outs are too anaerobic. We want to balance on the edge of being anaerobic while staying aerobic.
One way to accomplish this balance is with a LTHR test.
Learning your LTHR
There’s a saying that knowing your lactate threshold is as important as knowing the size of your bike. Lactate threshold is the point at which your body is building more lactate than it can flush away. Resulting in that burning feeling in the muscles. For example. Imagine we have a paper cup with a pencil sized hole in the bottom. When we pour water a rate that is the same in which it can flow out of the hole, this would be our aerobic capacity. Once our water flow rate is faster than the hole can flush it out, the cup begins to over flow. This is our lactate threshold.
Using a 10K Time Trial
Use this test to determine your LTHR. This will give you a true measurement of your Ride to 75 HR.
1) Find a road\trail that is either flat or has a slight incline.
2) Ideally you want it to be 10K in length or 6.2 miles
3) Start with a good 15- 20 min warm up
4) Hit Lap or restart your HR monitor when you begin your 10K time trail
5) Go as hard as you can for the full 10K
6) Record your average HR at the end of the 10K
7) Repeat this process in a number of different conditions
Your RPE should be high 8-9 maybe even 10, so long as you don’t pass out on the road. Once you have repeated this test 2-3 times you should have a good idea of your time trial HR. Now divide this number by 102%. This will give you your LTHR limit.
For Example: If my average HR over 3 x 10K time trials is 176 bpm. 176 / 1.02 = 172 bpm This is my LTHR. Now I can take my Ride to 75 hr and my LTHR and ride between these numbers to ride along the edge of my aerobic zone.
Now you have an exact HR zone and RPE to burn more fat
We want to ride on the edge of our aerobic zone. This is to maximize fat burn on the bike and increase fat burn or EPOC off the bike. We know that in order to increase EPOC our RPE needs to be high. But if our exertion goes to high the mitochondria, our little fat burning machines, block fatty acids from being oxidized. Thus its important to keep the RPE low enough to keep the mitochondria’s doors open during and after our ride. This is what we call riding on the threshold.
When it’s time to move on
Once you reach your weight loss goals and your goals shift to other specific events its time to think about a more structured plan with more varied levels of training and specificity based on your goals. This will also include the investment in a power meter. But working with Ride to 75 and your heart rate monitor, you will be able to enjoy your rides and burn fat until its time to switch goals.
Do you use a power meter? Are you just starting to ride with a heart rate monitor? Share your thoughts in the comments below.