Indoor Training – Heart Rate vs. Power
Becoming a stronger, faster rider is a common goal among many cyclists, and turning to data is a easy way to train more intelligently. Power meters have grown in popularity, with ‘Watts’ or ‘W/KG’ often heard being discussed in cycling groups. Should this be your go to measure if you want to take your training to the next level, or stick to the tried and tested heart rate training. I will be shedding some light on the pros and cons of both, and help you decide which is right for you.
We use heart rate or power outputs as data-driven indicators of how much work you’re doing. This enables you to tailor your training sessions to suit you and your goals, whether that’s increasing your base endurance or top-end sprint.
Training with Heart Rate
One of the great advantages is the ability to see just how hard your cardiovascular system is working. By knowing your resting heart rate and maximum heart rate, you can set the training zones on which to base your effort when working on a specific area of your fitness and form. This method is often used by those looking at sportifs or racing time trails, where it involves longer and steadier efforts in training.
- Easy to use & fit
- Easy to understand basic data
- Can be an indicator of fatigue, illness or overtraining
Is not always an accurate indicator of effort. If you’re feeling fatigued, ill or stressed, your resting heart rate will be higher. This means your training zones are going to be wrong, and you won’t hit your intended zones. Heart rate can also lag the workout, often taking a minute or two to rise to the level you’re aiming for and then stabilize. This can mean either putting too much or too little effort during key periods, such as short, intense intervals.
- Can be influenced by outside factors
- Susceptible to heart rate lag
- Heart rate straps can be uncomfortable
Warm Up – 10 minutes building up to 135bpm
3x Threshold Session:
– 10 mins @ 160bpm (90RPM)
– 2 mins easy to <135bpm
Warm Down – 10 mins decreasing to <135bpm
Training with Power
Training with power is less affected by outside factors and it produces an absolute figure whereas heart rate can fluctuate based on a range of factors. With a power meter, you can see clear progression. If put months of hard work into training, you can see clear improvements, which is great for motivation.
Unlike heart rate, there’s no lag with a power meter, and it gives you a consistent, reliable figure unaffected by external factors – the number of watts displayed on your computer screen is an exact reflection of how hard you’re pushing on the pedals. This ensures you’re working in exactly the right zones and you can be very specific with your training. “Training and Racing with a Power Meter”, by Hunter Allen is a great starting point for those considering this technique.
- More accurate reflection of effort
- Enables you to be more specific with training
- Makes motoring progression and fitness easier
While there’s more accurate and representative data to be gained, that data comes at a cost. Even if they have dropped significantly in price, power meters remain far more expensive than heart rate monitors. While the affordability of a heart rate monitor allows you to dip your toe into training with data, a power meter is a much more significant purchase, and some riders find training with power to be too prescriptive. Some people get a bit obsessed with it, too. You don’t want to become a slave to your power meter.
- Can be difficult to fit
- Data can be difficult to interpret
- Potential for reliability issues
Example Session(based on Function Threshold Power)
Warm Up – 15 mins building from 55% to 75% FTP
8x Speed Session:
– 2 mins @ FTP
– 2 mins easy @ 50% FTP
Warm Down– 5 minutes descreasing from 75% to 45% FTP