An interesting perspective that makes sense. Body types affect how we perform in all sports.

I'm 5'7 running 160mm cranks. I guess advantage for me being not that strong a rider is I'm rarely feeling like i'm on the 11t sprocket unless I'm descending.
Also what I've discovered is in comparison to my torso length my arms and legs are relatively short. Great for squats but not so much for reaching the bottom of the pedal stroke without compromise.

I'm 6'1" and have always run 175mm cranks on my mtbs.  With all the hype around short cranks, I finally tried shorter ones (165mm) and rode them for about 6 months.  I saw advantages on flat riding, but the majority of my trails are big climbs with big descents.  On the really steep climbs, I could never seem to keep my cadence fast enough to muscle my way up.  After watching this video, I decided to put my 175s back on and compare once again.  What a difference.  So much easier to just power up the climbs.  I probably went too extreme with 165s, but for me, I think 170s would be too short as well.  Lesson learned: go with your gut and not with what is trending at the time.

At 72 years of age, every human is different;
Raced with 175mm in the 1970s with a nominal cadence of 95
You have to look at the totality package, smaller steel frame, less weight, higher torque at the onset of a sprint and if one can no gear change during the sprint
For marketing purposes they want to put everything into boxes

I ride a 170 mm  crankset and have since I started racing in the mid-80's. I tried longer cranks for time trials and went back to 170 mm cranks. I raced track and used 170 mm cranks even in sprint. 165mm cranks never felt right. 170mm feels like a good compromise of torque and cadence. They spin up just fine, and grinding up very steep hills works too. I don't bike race anymore but still  ride. FYI - I am 5' 10" tall and have a lean muscular build. I was more of a sprinter on the road and did all events on the track but the kilometer was my best event.

Thanks a lot for your video that opened the discussion, and everyone sharing their experiences in the comments as well 🙏
I ordered cheap cranksets in 150, 155 and 160 to try them as I'm exploring options to address a hip impingement and low back pain on the same side after frequent long rides (4h+).
My usual crank size is 170 and I look forward to test the shorter one, now with more insight.
I've not seen anywhere else as much feedback on tradeoffs to look for when going shorter, I'm very thankful for that!

This is exactly what I found .
I’m 168cm, I’ve been on 165mm for 4 years. So my most recent build I opted for 160mm , Immediately it felt so natural , I wasn’t working to get the pedal over at any point. I could spin up so much easier and I found for short explosive efforts up to 2mins or so my power was higher and more constant . With the high cadence it was easier to create that initial  
inertia . However on longer efforts I found myself really struggling to hold my usual numbers . On a 20 min effort I was 10-15 watts less . I scratched my head for a while , blamed the PM at times but wasn’t till I jumped on my other bike with 165mm I discovered I could achieve my previous power zones .
Simply & You are correct , it’s basic physics, shorter cranks ultimately have less leverage .
So I have returned to my 165mm and all is good .

My bike fitter advised me against shorter cranks, but I tried it anyway and it resulted in more discomfort. I'm beginner rider and looks like full range of motion is beneficial for me. Maybe in few years when I get my position locked in I try again. I do prefer spinning over grinding.

Very well explained Charles. Shorter is indeed not an advantage for explosive efforts. Especially when considering the crank is part of the power transmission and a direct extension of your foot. In my case, I needed shorter cranks bc at 45 y.o. I already have stiff hips and I mostly do endurance rides.

Tried short cranks just couldn’t hammer the same so,
back to   175mm ❤

Rode 175 cranks in the 80s & 90s.  When I started riding again in 2014,  no one seemed to offer them.  172.5 came with the new bike.  I miss the longer cranks!

I 100% agree solid video. It sounds like you found your sweet spot and I recommend a lot of riders to do the same. I’m at 170 mm and I’ve tried 165, 172 1/2, and 175 mm cranks and 170mm suits me best.

Same here, I am 5'11", big guy, big quads, I played hockey for a long time. I tried going higher cadence but it just gets my heart rate very high and it drains my energy. I bought a used groupset many years ago and it came with a 175 mm crankset, I couldn't see any difference with my old 172.5 mm and I prefer to grind so I don't even car trying shorter cranks. I don't have any pain or discomfort whatsoever. The only reason I would go with a 165 mm crankset would be to open up my hip angle when I am in a tucked position because my knees touches my elbows sometimes.

as I'm a very average cyclists I can't even tell a difference between 165 and 170. Sometimes I thought I could, but also I've sometimes thought I was on 165s, but when I checked they were actually 170s. I'm 171cm in height for reference.

Good video. I'm also your height and noticed that for me, power intervals seated or climbing felt like I had more leverage with 170 than 165.  But that's because I don't usually spin a high cadence, but like a lower cadence for muscular endurance.  It's how I prefer to ride.

Didn’t work for me. Back to 170’s
Escape Collective wrote a great article on the forces required when changing crank length, well worth a read.

I like short cranks. I'm currently on 155mm, but I just got some 135's. All my cranksets are carbon and I'm 4'11

On the west coast of Canada, so first Hi fellow Canadian. I was racing many years with 175mm cranks. I have it on record have spun them up to 180 rpm. That said, this is said to not be something done easily, but with training, Just saying. Last year I switched my fleet of bikes to 165mm cranks. I have never had a 11x53 roll out, in fact I had a 54 matched with a 12 rear cog which is a smaller gearing overall than a 53x11. I now with 165mm cranks roll a 11 over with a 56, and will soon be on a 58 when available. My speed is up, my recovery is incredible off and on the bike, my climbing is better, which was a surprise , and I didn't realize I had hip issues till I switched. My average speed with minimal training compared to when race fit a decade ago is the same. Almost 60 years old next year Im going back to 1s and 2s which race together here.   I think that a couple things need to be taken into consideration with crank length, the shorter the crank the further back you will need your foot to cleat to get the same leverage. Also important is even with less leverage your legs are engaged in the power stroke sooner and arguably longer. Even if you feel you are not generating as much power, you are producing it longer within the cycle .

I went through the same sort of experience as Charles, and I live not far away, similar rolling terrain. I felt a bit off all year I was on 170s (I’m 185cm and a relatively low cadence, high torque guy) and just couldn’t convince myself 170s we’re working better for me than 172.5s and that’s only 2.5mm difference. I was on a rental with 175 recently, and they felt so stupid. Some riders will notice 2.5mm, others 5mm, others neither. Clearly there’s no rule of thumb that applies equally to all of us. We have to give options a fair shake to really determine what we want/prefer.

Was on 177.5 but age came and cadence dropped, been on 170 for a year, and shazam it increased! Not racing anymore so watts isnt my priority 😊. But no rider has the same proportion as another.
With shorter cranks my hips aint bothering me so its a win for me.