Mary’s question highlights another issue, we can get our heart rates highest in the sports that we are most efficient at. Because both Mary and I come from a running background our bodies are more efficient while running and thus better able to maximize performance and heart rate.

While cycling we are both less efficient and probably do not have the correct muscle groups developed enough to allow us to push our hearts to the limit.

Simply put, the legs give up through lack of strength before the heart does.

At 10km race pace for each stride you take it is suggested that you only use about 20% of your maximum muscle power, this explains why runners do not need large muscles and why Mary and I can get a high heart rate while running. However, cycling in a 40km time trial we can use up to 60% of our muscle power to turn the pedals, which means we need more powerful muscles to cycle. It is this lack of muscle power that is stopping us getting our heart rates higher, and leading to us to under achieve. We will both need to spend more time developing our maximum power-output to improve our efficiency on the bike.

One way to do this is the inclined leg press. Research suggests that if you have a weak leg press, in relation to your body weight, you will not be able to cycle fast. Being strong on the leg press does not guarantee that you will be a good cyclist, but weak performance will ensure you remain a poor cyclist!

Weight Training:

1. Aim to build up to 3 sets, start with lighter weights and only one set !

2. Do weights for 6 to 12 weeks

3. Do this twice a week as part of a strength programme

4. Pick a weight you could do about 20 lifts before reaching exhaustion

1. Leg curls 12 x 3 sets

2. Leg extensions 12 x 3 sets

Note: Your quads will always be stronger than your hamstrings.  should be 8:5 ratio. i.e. if you do extensions at 80 kg you should be at 50 kg for the curls.

3. Calf raisers 12 x 3 sets

Note: this will ache at about the 8th, last 4 should be tough.

4. Leg press 15 x 4 sets

Note: the aim to press about 65% of your one lift max.

In summary a lower than expected heart rate in one sport, compared to another, suggests a weakness that needs to be overcome in that sport. Although heart rate may help to highlight a weakness, don’t get too hung up on heart rates, as everyone is different.

On the bike it is more beneficial to monitor your average power output. While running, see what average times you can hold during interval training.

If you can maintain your target race pace, it does not really matter what your heart rate monitor is saying.

I received a letter from a lady new to triathlon, and it struck a chord as she has a similar issue to me. Both of our heart rates on the bike are much lower than while running. I have summarized her letter below. 

Mary was a top class runner with a 2.42 marathon and after that, 15 years as a successful rower. She will turn 50 this year.

“…running 3 x week similar my heart rate goes up to 160 maximum but on the bike even busting a gut my maximum heart rate is only 140. Usually hard intervals are 136 and a steady ride with a cadence of 90, the heart rate is only 110! – am I missing something – or is this because I am such a novice cyclist!  I am doing turbo sessions 3 x week and get out to ride for 2 hours if the weather is good – I have been cycling for one year.

Question – Do I go on perceived intensity (not very accurate) or do I need a maximum cycle test and then work off those heart rates for the bike? Do I just stick with this and hope the muscles will eventually respond?”

Talking about heart rates, introduces a very complex subject and I will quote my wife and I as an example to show, why we cannot just look up the answer in a book. My resting heart rate is 27.

Now I accept this is incredibly low, but is highlights a problem with training by heart rate alone.

If I double my resting heart rate, it is 54. If I double it again it is 108. Amazingly this is about the maximum pace that I do my easy runs at. It is also a heart rate that I currently find very tough to cycle at. My easy cycling is nearer 90 beats per minute. So, my easy running heart rate is the same as my interval training heart rate on the bike!

Let me take my wife Rieko, as another example. Her resting HR is around 50. If we double it, it is 100, double it again that is 200. This is in fact her maximum heart rate.  Where as I can double my resting heart rate twice and still be doing an easy run, if Rieko doubles her resting heart rate twice she is running all out.

At 27 beats, per minute my body is able to pump enough blood around itself for me to function adequately at rest, while Rieko needs 50 beats.  But for my easy run I must raise my heart rate 4 times my resting pulse, while Rieko must only raise her resting heart race two and half times. So a heart rate of 90 on the bike, although an easy ride for me, is in fact 3 times my resting heart rate. For my wife working at 3 times her resting heart rate, this would give her about 150 beats per minute, which is somewhere near her anaerobic threshold, or her triathlon race pace.

I hope I am starting to show that all our heart rates and bodies are different, and listening to our own body is much more effective than blindly following what the monitor or text book says we should do. Although HRM’s may have some good points they are just a tool, that would be better understood by using them less frequently, and by listening to our bodies more often.