After some years of organising WordCamp London, this year I was invited to speak instead. I took the opportunity to run an experiment on my public speaking fear, and see how my heart reacts to the stress of being on the stage.

I love writing, and public speaking is really not my daily cup of tea. However, last year I decided I’d step on the stage and share my knowledge with the awesome WordPress community. I gave a couple of talks, and I could really touch and feel the notorious public speaking fear.
The public speaking fear is like a 100m race
The public speaking anxiety, although peculiar, is similar to the moments you feel when about to run the 100m: the adrenaline pumps your heart, your brain might get foggy, your attention narrows down to the only mission you have to accomplish–run as fast as you can and cross the finish line.
When you’re speaking in public, though, the pressure on your body and mind lasts for more than 12 seconds: all things considered–prep time, introductions, the talk itself and the Q&A– you can stay under pressure for more than an hour (given your talk is 30 minutes long)!
Adding up to the public speaking anxiety: the personal matters
On top of the usual tension and fear of public speaking, the focus of my talk added more anxiety on me. In fact, my presentation was about how deal with face-to-face (or videochat) conversations with users. This has been one of the most challenging tasks I’ve dealt with at work, and questioned my ability as a professional. I went through one of the lowest times in my working career at Automattic, and I want to share this personal and professional downtime in the hope of helping people overcome their insecurities and avoid the mistakes I made.
This was no joke at all to me, and I knew that my body (and mind) might react in mysterious ways to that. Since I like experiments, I wore my MyZone waist belt whilst on the stage. I use this device every time I train to monitor my heartbeat and check on my efforts.
The device provides interesting data such as the heartbeat minute by minute, the percentage of efforts and the peak/no-peak times, calories burnt (calculated considering my personal/body data such as gender, height, weight, age etc) and much more.
I then stepped on the stage with my waist belt on, and after the talk –which luckily has been quite a success! You can check the slides here– I downloaded the data right away. I was quite surprised to see them. I was expecting some high peak in my heart rate, but I’ve never imagined that the public speaking fear would have my heart react this way.
Tracking the public speaking fear – how my heart behaved
Upon checking the results on how my heart reacted to the public speaking fear, I found out that in an hour of stage performance I have basically done a full body workout! Look at the stats here:
Leaving alone the MPEs
data, which is related with some MyZone specific settings, you can see that during a little bit more than one hour of performance my average heart effort was 61%. I burnt nearly 500 calories! *_insert :whoah: emoji here_*
By looking at the peak and average heart rate, the data are interesting as well:
If you consider that my resting heart rate is normally between 41 and 48 bpm, 159 is a hell of a spike – and I was just standing and talking.
If I look deeper and scroll how my heart pumped during the entire presentation, I can exactly go through my talk event from the MyZone stats. Look at the video below:
- Before 11:20 I am getting prepped with microphone setups etc. My heart is between 50% (grey area) and 60% (blue area);
- At 11:20am I’m introduced to the audience by the MC. The talk is about to start. My heart spikes to 82% of its effort (yellow area);
- During the presentation my heart remains steady at 70% of its efforts (green area). Only at the end of the talk it lowers down to 60%, which lasts also during the Q&A.
- Heart goes back to “normal” 50% effort once the Q&A is finished.
You may think that burning an extra 500 calories when giving a talk to an audience it’s not a big deal. I think it is indeed: you can understand how stress factors (in this case the fear of public speaking) can affect your body. In fact within a 90-minute upper body workout I burn a minimum of 700 calories. 500 calories when public speaking is a crazy amount of energy burnt.
In conclusion: I can control my public speaking fear now
You can be affected by the public speaking fear in many different ways. The support and attention of my MC, Hannah, helped me stay comfortable at all times, and feel less tension the minutes before stepping up on the stage.
Finding out how my heart and body acted while performing my talk made me realise how stress factors can alterate your thermogenesis and physiology.
On the other hand, it also helped me realise that feelings like anxiety and the heart pumping hard are natural reactions. It’s okay to be nervous when public speaking, there’s nothing odd or unusual in that.
The next time I’ll step on the stage I’ll be definitely more aware of what’s going on, and then I’ll be able to be more present, and control my feelings and my body reactions.
…and I’ll make sure to add a +500cal plate of pasta at the end of the speaking session to make up for the energy lost!
PS: I made a video with my report of WordCamp London. Watch it, and if you like it give it a thumb up and subscribe to my channel!