Why Training With Heart Rate is Still Relevant
Heart Rate Training Is Not Dead
Like so many areas in our lives, the pace of innovation in cycling is accelerating. Power meters were once a rare sight anywhere outside of the pro or Olympic team ranks; now they are ubiquitous at the Saturday coffee shop ride. But this has led to a few misconceptions, both for athletes with power meters and those without.
Misconception #1: Heart rate is not a good indicator of intensity
Heart rate is not as good or as precise an indicator of intensity, compared with power, but there are a lot of athletes who are unwilling to pay upwards of $1000 for a power meter. Can you train effectively with only heart rate? Yes. You just need to understand what a heart rate monitor is telling you and how you can use that information.
During exercise your heart rate is your body’s response to the work you are doing (power is a direct measure of that work). After more than 20 years of working with power meters we know a lot more about the nature of that response, and that has improved the efficacy of heart rate training. For instance, heart rate data from the field test that CTS uses with athletes (two 8-minute time trials separated by 10 minutes of easy spinning. Click here for CTS Field Test Instructions and Workout Descriptions) correlates strongly with power data from the same test. This means that the following calculations using the higher of the two average heart rates from your time trial will establish training intensity ranges that are equally effective for targeting your aerobic system, sustainable pace at lactate threshold, and repeatable efforts at VO2 max.
|Interval||Physiological benefit||Intensity range (% of Field Test HR)||Tips: Your Field Test heart rate is not the same as your lab-measured lactate threshold heart rate, so the calculations based on this heart rate are specific to this field test.|
|Endurance Miles||Base aerobic fitness||50-91%||The 91% is a ceiling to account for variables like hills during endurance rides. Aim to stay at 60-75% during the majority of your ride.|
|Tempo||Aerobic power||88-90||Cornerstone aerobic power workout, intervals should be long (20-45 minutes), with as little interruption as possible|
|SteadyState||Power at lactate threshold||92-94||Cornerstone workout for developing max sustainable power. Intervals should be 10-20 minutes each, with recoveries half as long as the intervals.|
|ClimbingRepeat||Sustainable climbing power||95-97%||Same energy system target as SteadyState; the intensity range is higher because of the extra muscle involved in climbing.|
|PowerInterval||Power at VO2 max||101+||Heart rate will lag behind your effort during these are short (1-3 minute) max, so to do them correctly you go as hard as you can and only use HR data for evaluation afterward.|
Misconception #2: If you have a power meter, you don’t need to monitor heart rate.
A lot of power meter users no longer wear heart rate monitor straps even though every power meter is equipped with heart rate monitor technology. But without heart rate, you’re gathering power data out of context. Heart rate data informs you about your body’s response to producing power. Today you might complete SteadyState intervals at 250 watts, an average heart rate of 165 beats per minute, and a perceived exertion of 7 on a scale of 1-10. Tomorrow you might be able to complete the exact same intervals at 250 watts, but at average heart rates of 160 bpm. If perceived exertion is still 7-8, I’d tell you to keep training. The power and PE are right, and the decreased HR is likely due to an increase in plasma volume as a response to yesterday’s workout. However, if PE is 9-10 and you feel like you’re in a time trial to produce 250 watts at 160bpm, the heart rate and RPE are indicators of significant fatigue and a need for more recovery.
Perceived exertion – and even pace – can provide context for heart rate for athletes without power meters. If HR is decreased to 160bpm (which can happen from increased plasma volume, interval workoutson back-to-back days, etc.) but your perceived PE and pace are normal for SteadyState intervals, continue at 160bpm. One mistake athletes often make is to push harder in an effort to achieve their goal of 165bpm. PE goes off the charts, but what they don’t realize is that power output does too. Instead of 250 watts they’re doing intervals at 260-270 watts, which is higher than they can sustain for those intervals. Instead of 3 high-quality intervals, they’re fried after one.
Heart rate response during intervals can also tell you whether you should continue with your workout or change your plans. When an athlete has recovered from previous training and is ready for today’s workout, heart rate will increase quickly as an interval begins (you should reach your target heart rate within 30-45 seconds). If your heart rate is slow to respond initially and stays elevated longer than normal into your recovery period, it’s a sign of fatigue. More often than not, you’re better off saving your hard interval sessions (SteadyState or harder) for another day.
Additional guidelines for heart rate training
- Be aware of cardiac drift: heart rate will gradually creep upward during a workout, especially in hot weather or indoors in a warm environment. This is a response to dehydration and an increase in core temperature; your heart beats faster at a given power or effort level. The increase can be 5-10 bpm in a hard one-hour workout, or up to about 15bpm during a 3+ hour ride.
- Heart rate is not a good indicator of intensity for some workouts: Sprints and 1-3 minute PowerIntervals (max efforts) are so short that heart rate doesn’t respond quickly enough to provide meaningful information during the actual effort. But since they are also maximal efforts, there’s no need to worry about data during the interval. Just dig in and go!
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I train with two things: myself and my bike. I find it relevant.
When doing EM or tempo rides and encountering hills, it’s almost impossible to keep my heart rate below 92% of field test heart rate. Is this normal, and what should be done about it?
If you monitor both power and heart rate, what is the correct action when there is significant heart rate “drift”? Maintain the target heart rate and let power fall, or maintain target power range and ignore the rising heart rate within some limit like an extra 10-15 bpm?
Have the same problem. I would also like to know the appropriate action to take 🙂
I have had a very difficult time finding a chest strap that will work with my pacemaker and heart medication. I finally found a device that works great: The MIO Link wrist strap. It works just like a chest strap, but uses optical light. It has really helped my training to map my heart rate and power together. Anyone that has issues with chest straps, I recommend the MIO Link (http://www.mioglobal.com/Mio-LINK-White–Heart-Rate-Wristband/Product.aspx?ProductID=15&DeptID=1).
Great article… Appreciate you sharing this insight. It helped me understand the core difference between the beneficial aspects of power and HR.
great article on heart rate. thanks