"Without external energy (but with external device attached)" is ... a bit disappointing. At what point does it cease to be running and start to be run-assisted catapulting? Or catapult-assisted running? It seems like more than just running.
As the father of a 6 year old who's never (yet) shared Naruto with my son, it's remarkable to observe that small children innately know how to do the Naruto run. Tragically, most children seem to forget the truth sometime around middle school age.
To be serious, though, the article suggests:
> Cycling is faster than running partly because the rolling motion of the wheels prevents collisional energy losses from stepping, but also because wheels can support the weight of the body in place of the legs, while pedals enable the human to supply energy continuously in the air instead of intermittently when the leg is on the ground.
but I think they miss the point by focusing on the last element rather than the first. I have lots of experience with running (where reducing ground contact time is often advantageous for efficiency), with cycling with clipless pedals where I can supply energy continuously, and with cycling with flat pedals. On the bike, I can sprint on the flats to about 16 m/s or 36 mph while clipped in. I don't do hard workouts nearly as often on flat pedals, so the data is more spotty, but I know I can reach at least 14 m/s or 32 mph; I'm just about spun out but typically not in my highest gear. I've never specifically tried to do a short-duration time trial on flat pedals, it might be higher than that, but it's not more than a 10% differential between intermittent and continuous connection to the pedals.
But running? In my prime, I could barely hit 9 m/s or 20 mph (I'm not and have never been a sprinter). If you tied a rope to my chest and towed me to 36 mph (using the rope to eliminate energy loss to air resistance) I'd be road pizza after a single step.
I can go faster on a pair of roller blades or ice skates, with one foot at a time providing an inefficient combination of sideways and rearward thrust, or a kick scooter using only one foot, than I could ever hope to run. The problem is not about the intermittent application of force, it's all about the need to convert angular velocity of your joints which has a very limited effective range into linear velocity over the ground. It turns out that cranks and chains over sprockets of various tooth counts are a great way to do this.
The problem is that confidently wrong comments are posted to social media like HN and Reddit so frequently that you'd actually be wrong assuming sarcasm most of the time.
So now you're just admonishing someone for trying to engage a comment instead of identifying the epic "anime run funny" humor.
IMO the sanest policy is to just allow people to respond earnestly to posts even if it might be a joke.
The person you are replying to was (probably) making a joke. Naruto run is an old meme.
I think they get the idea of what the article is describing going off of the full comment.
What you said is probably similar to what they said at the early invention of shoes.
Professional runners today already use an "external device," aka running shoes. If they ran barefoot or even wore mediocre shoes, they would perform worse. As long there's no external energy powering the device, I'd still consider it running.
With respect to the way this article presents efficiency, I would actually expect Naruto running to be slightly more energy efficient than regular running -- the further forward that one can lean while running, the more that gravity will contribute to forward momentum.
"Without external energy (but with external device attached)" is ... a bit disappointing. At what point does it cease to be running and start to be run-assisted catapulting? Or catapult-assisted running? It seems like more than just running.