Understanding pulse (Heart Rate) and why it differs

I have a very close relationship with my pulse. I know how watt zones correspondes to pulse, and it usually stays within its regular patterns. I have picked up that some people talk about having a very high pulse when they feel bad or sick. That has never happened to my! Quit the opposite. The really good days when i can push hard I find I can drive my pulse up to almost (cycling) max, when i feel worse its like my pulse just stops 10 beats under what a good day will be, even though (it seems like) i am pushing watts. It could be that i am choosing harder gears those days, and thats also whats keeping the pulse down. How can pulse be understood? I know its not a very stable metric to pay too much cncerns too, but for me not being able to drive my pulse up = need to rest/slight cold or something nots right.

Would love to hear how other experience pulse :slight_smile:

As you alluded to @Silje heart rate (as we commonly call it in “sports-speak”) is very individual and also can vary for a large number of reasons. It can vary based on what you ate, how you slept, how warm/cold it is, how stressed you are, how well-rested, and even depending on what you are thinking about!

From a study on the topic: “HR measures are determined by multiple influencing factors, such as environmental (e.g., noise, light, temperature), physiological (e.g., cardiac morphology, plasma volume, autonomic activity), pathological (e.g., cardiovascular disease), psychological (e.g., mood, emotions, stress) conditions, and non-modifiable factors (e.g., age, sex, ethnicity), as well as lifestyle (e.g., fitness, sleep, medication, tobacco, alcohol) and determinants of physical activity (e.g., intensity, duration, modality, economy, body position)” (Sandercock et al., 2005; Buchheit, 2014; Fatisson et al., 2016; Sessa et al., 2018).

And the most important part:

"[…] a recent meta-analysis found that the direction of change [in heart rate] was the same for both increased and decreased performance (Bellenger et al., 2016). For example, vagal-related HRVrest increased parallel to both increased and decreased (aerobic) performance, representing either increased parasympathetic modulation or parasympathetic hyperactivity. Similarly, decreased HRex was observed in both concurrent performance increases (Buchheit, 2014) and overreaching-associated performance impairments (Bosquet et al., 2008). To date, the only promising approach for deciphering this dilemma lies in the contextualization of HR measures and the use of multivariate approaches (Bosquet et al., 2008; Lamberts, 2009; Plews et al., 2013; Buchheit, 2014; Bellenger et al., 2016; Capostagno et al., 2016; Bourdon et al., 2017; Hottenrott and Hoos, 2017; Thorpe et al., 2017; Coutts et al., 2018; Kellmann et al., 2018).

I other words, the way HR changes can be exactly the same wether you are fatigued or are performing better! Therefore, from a practical standpoint, you should not worry too much about HR and should not use it in isolation to determine if you are ready tp train or need to rest. You may use it in combination with other factors.

Joe Friel, in the latest edition of his book, The Cyclist’s Training Bible, has a helpful table listing the factors to take into account when determining your readiness to train, and gives a 1 or 2 score to each, so that if you have a total score of 7 or higher, you probably need to rest that day (p.178, Table 11.1):

Common morning warning indicators that should be taking into account:

  • Appetite - very high/very low?
  • Waking pulse- high?
  • Enthusiasm vs. just wanting to stay in bed
  • Motivation to train
  • Overall feeling (fatigued? stressed?)
  • Mood (unusually grumpy; easily angered?)
  • Sleep (duration and quality)
  • Health
  • Muscles/joints (soreness?)
  • Heart rate variability (not the same as simple heart rate)

A fairly new product on the market that claims to help athletes track their readiness to train via Heart Rate Variability and sleep quality is Whoop. I have not used it, so cannot provide my opinion.

I hope this provides some background!!

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Thank you for using your time to answer questions like these in depth. I have actually started to use HRV measurements with HRV Elite and my waist strap. I use it out of curiosity to understand better whats going on, and if there is a pattern i need to know about to better manage my training and life in general. I understand and I have read about it on some level and i also understand its not the answer to everything. Just getting data from my body like that is amazing!

In all the workouts until now (i did 3.1 today) my HR has been on the lower side even though a lot of work has been way above threshold in terms of watt. That triggered the question…

When was the last time you updated your FTP?

I did a ramp test in august and then one in september. I put my FTP down a little bit after i was feeling overtrained/ sick for three weeks leading up to the challenge. I turned it slightly up again last week so its almost near my september FTP. I may need to do a ramp test maybe on Sunday. That being said, i think i do my intervals generally on the higher side of the target (+ 10-15 watts) so maybe i should just put my september ftp in TP/Zwift again…

I would recommend keeping your FTP where it’s at until the end of the challenge… then you can do another test if you would like, or go back to the previous higher FTP.

Okay thanks! Thats a plan!