 Are clipless pedals actually more efficient than flat pedals? Today we'll be reviewing the science to answer this question and at the end of the video I'll be discussing the practical applications of the research. The answer might surprise you. Welcome back to another video, my name is Dylan and for weekly science based cycling videos just like this one be sure to subscribe. Clipless pedals are named that way because they attach to your shoe without the use of a toe clip and strap. Theoretically, having your foot attached to the pedal is more efficient because you're able to pull up during the upstroke while pedaling. That's the theory anyway. A couple weeks ago though I did a video on pedaling technique in which I talked about whether or not pulling up during the upstroke is actually more efficient. For those of you who missed that one, let me catch you up to speed. This study measured the pedaling technique of elite 40km time trial as the workload increased to race pace. They found that pulling up did not contribute significantly to external work done because roughly 97% of total work was done during the downstroke. Remember that these were elite pro riders in this study. Even the fastest riders in the world don't seem to do a whole lot of pulling during the upstroke. These sorts of findings on elite riders are confirmed in further study and in studies where riders are told to pull up during the upstroke, even though mechanical effectiveness is improved meaning that torque is applied more evenly throughout the pedal stroke, efficiency actually decreases. Essentially pulling up during the upstroke is somewhat surprisingly not all that important. This is because the flexor muscles or the muscles in the leg that bend the knee are not nearly as efficient power producers as the extensor muscles which are used to straighten the knee. It's not unreasonable to assume then that perhaps having your foot attached to the pedal is unnecessary and just maybe that $400 pair of cycling shoes was a complete waste of money. Dude, first rule of cycling, faster or not anything that makes you look more like a pro who didn't pay for their equipment is worth paying for. This sparked some questions and some debate in the comments section about clipless versus flat pedals, so I thought this video would be a good follow up. While I and probably 90% of serious cyclists would never consider using flat pedals, it would be interesting to know whether or not clipless pedals are actually doing anything for us. So without further ado, let's jump into some science that investigates this very question. This study on gross cycling efficiency with and without tow clips tested sub-maximal oxygen consumption with subjects used flat pedals and when they used tow clips and straps. And what they found was actually incredibly surprising. Rather than being lower as one might expect, the mean VO2 was actually 2.1% higher when subjects used tow clips. Essentially, using tow clips did nothing to improve efficiency and if anything efficiency actually went down a little bit when subjects used tow clips. Now there are some major limitations to this study. First, the study used recreationally active males. These are not necessarily cyclists and in fact they probably aren't or else the study would have said so. This is important because there is a possibility that trained cyclists would see more of a benefit from clipless pedals since they spend so much time training with them and may have developed more of a pulling up technique. Also this study used tow clips, not clipless pedals, and it seems logical that stiff cycling specific shoes and clipless pedals would be more efficient. At least that's what cycling industry marketing has taught me. Luckily we do have similar studies that address these concerns. This study on the effect of shoe pedal interface used experienced cyclists to test the metabolic cost of cycling with three different pedal shoe combinations. Running shoes with flat pedals, running shoes with tow clips and straps, and rigid sole cycling shoes with clipless pedals. Dude, I swear if this pedal that looks like it came off my grandpa's rusty old 10 speed is just as fast as a speed play pedal, I'm gonna freak out. What they found was that across power output there were no significant main effects of shoe pedal condition on metabolic power consumption, oxygen consumption, or RER. In conclusion they state we recognize that many riders simply prefer cycling shoes and clipless pedals for comfort and safety but our data refute the claims of improved efficiency via rigid sold cycling shoes with clipless pedals. In summary we found that different shoe pedal combinations had no significant effect on the metabolic cost of cycling. That's it, I'm out. Nope, unsubscribed. Again, having your foot attached to the pedal whether it be through tow clips or clipless pedals doesn't seem to improve efficiency. However we have only looked at two studies so let's see what further research has to say before we come to a conclusion. This study on pedal type and pull-up action during cycling used both elite cyclists and non-elite cyclists. They tested flat pedals, clipless pedals, and pedal feedback in which subjects were instructed to pull-up on the upstroke. They found no significant difference for pedaling effectiveness, net mechanical efficiency, or muscular activity between flat pedals and clipless pedals. When subjects were told to pull-up on the upstroke efficiency was actually reduced which confirms what other studies have found. If you're surprised by the results of this study, well so were the authors of the study. They state that the lack of difference between pedals without tow clips and clipless pedals is somehow surprising. Indeed, none of the kinetic quantities showed any difference between flat and clipless pedals, even for elite cyclists who are used to cycling with clipless shoe pedal systems. That may be the most telling aspect to this study. Easily riders average over 19,000 kilometers a year using clipless pedals and still they weren't able to find a difference in efficiency when they switched them to flats. The research on efficiency of flat versus clipless pedals is limited but all the studies seem to point in the same direction. The closest we get to seeing a difference between clipless and flat pedals is this study on the difference in EMG activity between clipless and flat pedals which found less EMG activity when clipless pedals were used. This study didn't look at efficiency though. This may be another one of those instances where something that we all take for granted turns out to not be the case when we actually look at the science. That being said, there are some potential drawbacks to the science in this particular situation. For starters, all the tests were done on stationary bikes. None of them tested clipless versus flat pedals for climbing or high intensity efforts like a five minute max test or just a flat out sprint for example. And we know from studies done looking at pedaling technique that your pedaling style and the activation of your muscles can change while climbing or under high exertion. It would be fascinating to see some studies addressing this because these seem like the situations in which clipless pedals really shine. Clipless pedals may also offer additional comfort and injury prevention over flat pedals. This study on plantar pressure and cyclists looked at pressure on the foot using clipless and toe clip pedals. What they found was that clipless pedals produce higher pressures which are more spread across the foot. This may be important in the prevention and management of overuse injuries in the knee and foot. Clipless pedals are not without their problems when it comes to overuse injuries though. For some having their foot locked in place can cause issues but usually these issues are resolved by having a cleat with more float. This study on clipless pedal float on knee injuries and cycling collected pedaling data from cyclists with and without knee pain. They found that the largest applied moments were observed when clipless fixed pedals were employed while clipless float pedals significantly attenuated the applied moment. And cyclists with chronic knee pain exhibited applied moment patterns markedly different than the group without knee pain. Pedals with more float reduced this without compromising power transmitted to the bike. This review on biomechanical factors associated with shoe pedal interfaces confirmed these findings concluding that recent scientific investigations support recommendations to use float systems either to alleviate existing cycling related knee pain or as a preventative measure. And contrary to concerns in the cycling community regarding power loss associated with float systems effective force transmission is not compromised at the shoe pedal interface when float systems are used. Essentially using pedals with a reasonable amount of float is a good idea for preventing overuse injuries. If you already suffer from knee pain this is especially important. And no having pedals with a lot of float won't compromise your power output. That's the research but what are the practical applications here? Should we throw away our expensive cycling shoes and pedals in exchange for flat pedals and sneakers? Well first we need to keep in mind as I said earlier that none of these studies tested climbing or sprinting. And I'm not really sure that a test needs to be done although it would be interesting. Just go out and try to sprint as hard as you can with flat pedals and it won't take you long to realize that this is a bit awkward and you may even find your foot lifting up off the pedal. Not what you want when you're doing a max effort. On the flip side plenty of experienced mountain bikers choose to ride flat pedals although it has more to do with confidence while descending than it does climbing or sprinting ability. That being said if you are a mountain biker who uses your flat pedals as an excuse for why your buddies had to wait for you after a pedaling section well they probably made way less of a difference than you think. Yeah maybe if they spent more time pedaling to the top instead of shuttling every time they'd be faster climbers. The only time I take a car is when I'm trying to steal a KOM. Wait no I mean clipless pedals may also help with comfort and injury prevention. Because your foot isn't attached to the pedal with flat pedals your foot may be in a slightly different position every time you use them. Bike fitters who obsess about cleat position are cringing right now just thinking about that. This really only becomes an issue though when you really start doing big miles. Also if you use sneakers instead of dedicated flat pedal shoes there's a ton of flex from the shoe to the point that the shoe almost wraps around the pedal definitely not ideal and could cause problems. Finally and this point is for the more serious riders who are gonna use clipless pedals anyway clipless pedals and shoes are substantially lighter than flat pedals and shoes. So do I recommend using flat pedals? For most serious cyclists and cycling situations, no. However it is interesting to know that clipless pedals actually aren't more efficient than flat pedals at least when pedaling down a flat road at a moderate pace. At the very least perhaps it'll be a good conversation starter at the group ride so you won't have to talk about how high your FTP is for the hundredth time. I feel like that was directed at me. Thanks for watching. If you enjoyed this video be sure to give it a like, subscribe and share it with your cycling friends. I'll see you in the next one.