Interesting fitness data from a session of sim racing

Thought you guys might find this interesting, and thought maybe it warranted it’s own topic…

Like many of us, I have jumped back into iRacing lately since I am not doing other racing. I also have been wearing a Whoop band for the past couple months to track fitness and sleep. If you don’t know what it is, basically it’s like a FitBit without a screen, and you wear it 24/7. It monitors your heart rate, sleep quality, and a bunch of other metrics that it then converts into data and charts to analyze and recommend training or sleeping habits.

I ran a quick race in the Miata yesterday to get back in the groove, and it was the first time I have worn the Whoop during a competition session. I built a surprising amount of Strain, which is Whoop’s term for cardiovascular load. This is my 20 lap Miata race from Lime Rock:

The calorie burn isn’t always super accurate, but the heart rate always seems pretty spot on. For reference, when I ride my bike on the trainer at a fairly brisk pace, I build about 10 Strain in 30 minutes.

Cool to see the heart rate spike at the start, level off when we spread out and settle into a groove, and then start climbing again at the end. For the last 8-10 laps I was hunting down the guy in front about .1-.2 a lap and the guy behind me was closing up on me, so it got tense.

Being skinny-fat, I never paid much attention to this kind of thing until recently, but something like this might be valuable data to not only help train your physical fitness, but also mental and emotional fitness during the course of a race as well.

Anyone else use a fitness tracking type band while they are sim racing or real racing?

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I have that garmin which I used once or twice in actual karting. I’ll try to find it and see if my sim is more than a blip. I suspect it’s not. I run pretty high ffb these days and my body moves quite a bit. Likely more than I think, more than watching tv, but less than beat saber. Probably closer to beat saber.


That’s super interesting. Very interesting to see how the heart rate settles down, I wonder if during a kart race if it would settle down like that too?
I’d love to see a comparison.

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This is cool stuff. I have a Garmin watch that I use when working out, and intend to use it while karting too. Was out for a recent test day, and unfortunately forgot to bring it with me. I did happen to go with a pro driver for whom @tjkoyen has recently painted some helmets, and he was wearing a Whoop band throughout the day. His HR in a shifter kart at a small track was between 130-160, seemingly spending the most time in the 140-ish range. This was just practice, so I suspect HR would be higher when racing, and in the heat of battle.

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Lando norris just said he gets more nervous on sims than reality too. I am the same really.

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The few iracing Miata series races I did were spectacularly anxiety producing prior to the start. I don’t know why I was so much more nervous than irl. Fairly ridiculous considering it’s virtual and no one but yourself cares how you finish.

It is odd, I would agree that my heart pumps harder before an iRacing start than it does when on grid for a kart race. Not sure why that is. Maybe it’s just familiarity. I’ve done 100x more kart races than iRacing.

In my case, I don’t recall, even in my first IRL kart race, that sense of impending chaos and anxiety. And, it was justified. I was punted in all 5 I-races I did. :sweat_smile:

I just did my first few iRacing events last weekend and I was not expecting to be as nervous as I was. I definitely was more anxious about that than I remember being about any real life kart race.

Now that you are turning into an alien… what’s your experience with nerves and iracing? You are top split now, so I am guessing you have at least 100 races under your belt?

You may recall me freaking the heck out when I was messing about in Miata. How did it go for you, initially and now?

I found my garmin and if I can find the charger I’ll get some data re KZ sim at 50 and 100% ffb. It is not negligible but of course, no lateral loading. I suspect my bpm go up and stay up, even in sim.

Anecdotally, I have to use a fan when hotlapping seriously. Which suggests there’s some level of real exertion.

In actual x30 racing, 180bpm was my peak.
According to the software, a race weekend was about 10k calories.

You’ll nearly always see an elevated HR just from the stimulation of the driving activity/adrenaline. At least a some point during a session anyway.

I’m not quite an alien yet, but doing OK for an old fart. I got out of Miata rookies in 16 races, joined the Skip Barber series for season 3, and made my way to the top split in about 17 races. But I’m still 0.3 to 0.6 off the aliens depending on the track. It’s frustrating, but I guess I can’t feel too bad because Max Verstappen and AJ Allmendinger were in the same boat when I saw them in SB races. :grin:

Then I wanted a completely different challenge so this year I started dirt racing with the 305 Sprint Car. I got out of the rookie class in 12 races, and made it to the top split regularly after about 35 races. I can now run pretty much the pace of the aliens (track dependent), BUT, I still have much to learn about managing track changes through the race and doing ‘slide jobs’ when you can’t see a damn thing out of the right side of the car because of the wing. :flushed:

As far as the stress level goes, I think somewhere between 90 - 110 percent of my stress is related to the crap shoot of whether you will be racing against someone who respects the sport and their competitors, or someone who just ‘sends it’ regardless. That aside, I do still get a nice idrenaline hit whenever I fire up the rig.


Thanks for sharing that. Impressive work, doubly so for old farts like us.

Have you come across any of the big names in races yet?

I may join you and live out my sideways dirt sprint car fantasies in a safer manner.

Edit: finally, as an accomplished thinker and racer of cars, (formula ford as well as some other classes), what, in your mind, is the greatest hurdle a kart driver encounters when attempting to transition to cars?

  1. :heavy_dollar_sign::heavy_dollar_sign::heavy_dollar_sign:

  2. Relaxing into the much slower energy cycle of a car compared to a kart. (Moving energy in a car, while still fast, is a much slower process than in a kart because it weighs more and because it has suspension, which must be ‘loaded’ before the load needed for the tires to do their work can be transmitted to the tires.)

  3. Typically track time for cars is more difficult to come by, and more expensive than for karts, so extracting EVERYTHING possible out of every moment of track time (experience) is critical. Simple experience can produce rote learning and maybe some insights. However, when you shred ever piece of experience with critical questions (how, why, what if, etc.) then you will discover the next lesson(s) you need to advance, and you will more fully integrate the experience into your knowledge matrix… you will elevate rote skill acquisition to understanding, so its essence will be applicable in different circumstances.

Max and AJ are the biggest names I’ve come across on iRacing, but I did just finish beating former USAC Champ Brady Bacon in a sprint car race… pissed him off in the process too apparently. :grin:

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Thanks for the observations. The bit about weight and the energy cycle makes sense. When you lose the kart, it snaps, skids and stops. Cars you can feel the wave extend and it’s more deliberate and longer.

Nice work on iracing!

This is my biggest struggle in iRacing for sure. I’m always so eager to go straight from brake to throttle quickly like in a kart, and I have a hard time rewiring my brain to allow the car to coast a little and load up before I give it the beans.

I understand when I’m doing it wrong, but almost 20 years of muscle memory is hard to re-train, especially on a sim where I can’t feel the other forces at work that would normally tell me when the car is loaded or not.

I’ll slap my heart rate monitor on for the F1 2019 series this weekend when I try to send it past @DavinRS again :stuck_out_tongue:

I suspect this isn’t physical exertion but your brain telling your body to be ready for physical exertion, there’s plenty of study showing that simulation (via imagination or a computer) is the same for the brain as real life.

I get way hot driving a sim, but I don’t get anything like as nervous as a kart race. Most of my nerves in a kart race come from my self destructive need to know everything about my competitors and almost psyching myself out of the race. Can’t do that with a sim because most of the people are basically anonymous to me. Would probably be different if I was doing IRacing and I came across a famous name but I don’t…yet.

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I’m glad I’m not the only one having that problem. I catch myself either not turning the wheel enough, getting front lockups on turn in, or jumping to throttle too quickly. After watching one of my pro buddy’s in car footage it’s absolutely insane how different the driving style is compared to what I’m used to. It’s really easy to get frustrated.

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Does anyone run pedal vibrators? I saw someone setup little vibration motors on the throttle and brake pedals - that piqued my interest. Anything tactile that could alert you to wheelspin,or the very start of a slide, could program better muscle memory.