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I Spent My Sabbatical Building a Power Meter for Sledgehammers

leblancfg.com

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Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#71

Post by leblancfg »

hex4def6 wrote: post #60
leblancfg wrote: post #45

Aye, author here. Pleased it's getting visibility ofc, but ABSOLUTELY not expecting to get traction this early. Please pardon the AI-generated placeholder images and some of the text at https://intensity.systems , I'm still very actively working on that.

I'm curious about the units -- watts doesn't really seem right. It seems like joules would make more sense, right?

Both are needed, but for an athlete watts is by far the more useful feedback for training, and following the intended stimulus of workouts.

As a workout, "bike 30 km" is vague and meaningless. "bike 30km in 1h" is better, but not specific to the athlete: some have better cardio than others. Most serious cardio workouts are given in zones: "bike 1h at 60-65% of your functional threshold power" [1] – this particular workout would also be known as "zone 2 training session".

(1) https://www.trainerroad.com/blog/what-ftp-really-means-to-cy...

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#72

Post by leblancfg »

xcskier56 wrote: post #37

I could see this being used for fitness tests for cross country skiers. A very common exercise is med-ball slams. These aren’t a perfect analog to double poling but definitely close. Being able to track your one rep max force you can generate could be an interesting metric especially for sprinters

100% agree. And the issue with med-ball slams is they also can just be dropped in a testing setting, and the only power needed to be generated is on the "up" cycle. I wouldn't even trust my own med-ball slam benchmarks from one month to the next, as I'm not confident I slammed them with the same intensity.

I'm curious though, wouldn't a Concept2 ski-erg be the best machine for that job?

>track your one rep max force [...] especially for sprinters

Yeaaah that's the ticket =) One level of abstraction higher: you can think of that 1RM as the leftmost point on the max power curve, i.e. max force you've historically generated, from 5secs all the way to e.g. 60 mins [1].

(1) https://www.trainingpeaks.com/blog/4-key-uses-for-the-power-...

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#73

Post by leblancfg »

lucy_hnatchuk wrote: post #68

did you find any correlation between strike power and recovery — like, does the pad already give you enough signal to say "don't swing hard tomorrow"?

I didn't look into or find any myself, but "power meter enabled" sports like cycling, rowing, etc. have a way to measure the strain/fatigue of efforts relative to the athlete's fitness (FTP). Same would apply here.

There are various methods to measure that strain, e.g. Strava, intervals.icu, TrainerPeak all have their slightly tweaked implementations.

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#74

Post by leblancfg »

leblancfg wrote: post #71
hex4def6 wrote: post #60

Earlier quoted context omitted.

I'm curious about the units -- watts doesn't really seem right. It seems like joules would make more sense, right?

Both are needed, but for an athlete watts is by far the more useful feedback for training, and following the intended stimulus of workouts. As a workout, "bike 30 km" is vague and meaningless. "bike 30km in 1h" is better, but not specific to the athlete: some have better cardio than others. Most serious cardio workouts are given in zones: "bike 1h at 60-65% of your functional threshold power" [1] – this particular wo…

Thinking back, I should also add: if you're interested in how hard a single hit is, then yes joules!

I'm approaching it as a workout, where you're doing dozens of hit. Good idea to have an individual strike joule view to the display though! "carnival mode"

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#75

Post by markus_zhang »

ramon156 wrote: post #11
markus_zhang wrote: post #7

Earlier quoted context omitted.

Wish I could do that too. But sabbatical is usually reserved for the elite engineers in elite firms.

Work culture is so weird. What do you mean, it's reserved for the elites? In my country you get to build your holiday days, so I could totally take a month off if I don't take any other days off this year. Hell, we even have a website to perfectly time it here so you get the most bang-for-your-days. lmao. I will never comprehend this Silicon Valley mindset. You can also be a 10x engineer while drinking a martini in t…

You are right. I was mostly thinking about a sabbatical of about 3 months.

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#76

Post by MisterTea »

bee_rider wrote: post #33
MisterTea wrote: post #18

Earlier quoted context omitted.

> and 6+ months is pure fantasy:) I've seen this before. Had a vendor become helpless after their only engineer took a 6 month sabbatical. Had to cancel orders and switch vendors because they stated "Until the engineer returns, we can not quote a delivery time." Imagine being that company...

Kinda surprising they weren’t able to plan around that, surely The Engineer didn’t just decide randomly to go on a 6 month sabbatical all of a sudden.

It was a small vendor that was bought up into a larger umbrella parent so I'm sure there was no one at the helm capable of thinking ahead of making this months numbers.

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#77

Post by leblancfg »

digitallogic wrote: post #56

This is pretty cool! Your note about cycling power meters changing the way you perceive effort matches my experience as well. One other bit from my experience: I'm a runner and a cyclist, and I've always lusted after having cycling style data and prescribed workouts for my running. When Stryd launched I was all in, but... all it gave me was power numbers. It didn't have the tribal knowledge that came with my cycling…

Author here: funny you should mention that! Same idea has been on my mind for years at this point.

To me, the holy grail of sports training is to have simple but powerful enough models to estimate power data from dozens of movements, and fit various power curves that match real-world training.

So much promise there.

---

As for Stryd: That's so interesting. I'd imagine a lot of the same parallels to cycling to apply? Once you have your running CP/FTP, I'd imagine you could follow the same cycling training plans (relative to your FTP) for the same intended stimulus.

I'm curious though, can you see the Watts/zone/W'bal/etc. values on a watch or something when you're running?

Re: I Spent My Sabbatical Building a Power Meter for Sledgehammers

#78

Post by digitallogic »

leblancfg wrote: post #77
digitallogic wrote: post #56

This is pretty cool! Your note about cycling power meters changing the way you perceive effort matches my experience as well. One other bit from my experience: I'm a runner and a cyclist, and I've always lusted after having cycling style data and prescribed workouts for my running. When Stryd launched I was all in, but... all it gave me was power numbers. It didn't have the tribal knowledge that came with my cycling…

Author here: funny you should mention that! Same idea has been on my mind for years at this point. To me, the holy grail of sports training is to have simple but powerful enough models to estimate power data from dozens of movements, and fit various power curves that match real-world training. So much promise there. --- As for Stryd: That's so interesting. I'd imagine a lot of the same parallels to cycling to apply?…

Very much on the same page as far as the holy grail! Would love if I had all that data (and it was actionable).

As for the Stryd... take this all with a grain of salt because I only have a consumer level understanding but: You can establish your FTP, but then the issue is setting zones from there. My understanding is that the big thing with establishing them is having an accurate estimation of LT1 and LT2 lactate thresholds. Most zone calculators are approximating that, but those calculators are based on a large body of data comparing lactate levels to cycling power in a controlled environment (a lab). That large body of data doesn’t exist for running power, and I recall reading that the little bit that does indicates that formulas for cycling power’s impact on L1/L2 thresholds don’t line up with running power. It’s also been maybe 4 or 5 years since I was engaged with this so the science may have improved!

Watch wise, when I used it, I have a Garmin Fenix, and it had options to show watts/zones/etc. You can even plug in zone based workouts just like you can with cycling power. I did find it a bit of a pain to monitor on a watch vs a bike computer, but not too big of a deal.

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