Bike fitters love to remind cyclists that you only contact the bike in three places: the handlebar, seat, and pedals. Comfort matters in all of these areas, but only one of them is directly involved in propelling the bike forward. That makes cycling shoes one of the most important accessories you can buy.
But how much should you spend? What features should you look for? It can be hard to know, particularly with road shoes, where product marketing focuses largely on sole stiffness. The clear message is that stiffer is better. Of course, stiffer soles cost more, as do the sophisticated upper materials and designs that go with them. Road shoes start at around $75, with some models running more than $500.
But a more expensive shoe isn’t always better. And recent scientific research suggests that sole stiffness may not matter nearly as much as we thought.
Our goal here isn’t to tell you which brand or model of shoe to buy, nor to tell you that you have to spend a certain amount of money. Different riders have different needs. It’s simply to tell you that you might not need to spend as much as you think you do. Personal fit preferences aside, a hardcore criterium racer may appreciate the feel of a super-stiff shoe. But for most other riders, what matters most is a balance of stiffness, support, and comfort. In these cases, the sweet spot for road shoes—the point past which prices rise fast but additional performance per dollar diminishes—is $225. Here’s why.
Stiffness Isn’t the Benchmark
Road shoes typically have soles made from nylon, nylon and glass fiber, carbon-fiber composite with glass fiber, and full carbon fiber (these are listed in ascending order of stiffness). When shoe manufacturers harp on sole stiffness, they often represent it with some kind of score, like Specialized’s FACT rating or Shimano’s Outsole Stiffness index. These scales are relative, since they only apply to the shoes within a brand’s own line. According to Ashley Sult, a footwear developer for Specialized, its S-Works 7 shoe (FACT rating of 15) is about twice as stiff as the brand’s Torch 2.0, which scores a 7.
But those numbers have limited comparative utility. “They can be helpful within a brand, but they don’t work to compare brand to brand,” said Peter Curran, Giro’s cycling-shoes category manager. On its newest shoes, Giro now lists sole stiffness by Newtons of force per millimeter of deflection, which would offer an apples-to-apples comparison if other manufacturers followed suit.
More to the point, a trio of studies in the journal Footwear Science from researchers at the University of Colorado suggest stiffness may not matter nearly as much as we’re led to believe. All three studies originate from CU’s Locomotion Lab, a group of researchers who study the biomechanics of running and cycling, led by associate professor Rodger Kram. In the first, from 2016, researchers measured whether sole stiffness affected energy use during aerobic (sub-threshold) riding. They measured energy use as riders pedaled at 50, 100, and 150 watts while wearing Nike running shoes on flat pedals, the same shoes on pedals outfitted with toe clips, and cycling shoes with clipless pedals. Somewhat surprisingly, they found no statistically significant differences in metabolic cost. Even squishy, flexible running shoes were as efficient for pedaling as dedicated cycling shoes attached to clipless pedal systems.
Last year, another researcher tested almost the same setup at sprint-level power outputs, and found that, at that level of effort, there was a massive difference. Riders wearing clipped in cycling shoes sustained 25 percent higher average power output (about 800 watts) over a 100-meter sprint than they did when wearing running shoes.
You’d expect that. So yet another of Kram’s grad students tried a second sprint test of similar design, this time comparing three pairs of cycling shoes Specialized created for the test. (Specialized financially supports Locomotion Lab research but did not commission or fund this study. And the study doesn’t exactly bolster current cycling shoe marketing.) All three shoes had the upper and closure system of the Torch 3.0 paired to soles of different stiffness, from the Torch 2.0 (FACT rating 7), Torch 3.0 (FACT of 8), and S-Works 7 (FACT of 15).
The conclusion: there effectively was no difference. Peak power varied by 11 watts across all three shoes respectively: just one percent. Average power varied by six watts, which is six tenths of a percent. (Due to a shorter sprint interval of 50 meters, both values were higher than those from the other 2020 test comparing a running shoe to a cycling shoe). Other measurements, like peak torque, sprint velocity, and cadence, were also almost identical. “I didn’t expect to see the differences [that we saw in the running vs. cycling shoe comparison],” says Tripp Hurt, the masters student who led the research. “But I did expect to see some measurable difference.”
There are caveats to these studies, of course. They’re all small sample sizes, which somewhat limits confidence intervals for the results. (Hurt’s sprint study was accurate to within 16 watts.) They used trained male cyclists, whereas studies with a different subject group might yield different results. They focused on longitudinal sole stiffness, not torsional. And they were over limited intensities and durations: a few seconds of all-out sprinting, or five minutes of steady-state pedaling well below threshold power for a trained cyclist. Over longer time periods, differences in sole stiffness might produce meaningful changes, especially if fatigue or pain changed pedaling motion or increased metabolic cost.
But broadly, the results tell us that sole stiffness doesn’t matter nearly as much as we think it does. Hurt’s study hints at one possible reason: because power is applied to the pedal through the ball of the foot, there’s no bending moment to flex the whole sole plate. In other words, even if a sole is relatively flexible, the biomechanics of pedaling mean we don’t bend it much even when sprinting at full power.
What to Look For
What seems to matter, then, is a reasonably stiff sole at the point of power transfer, and a secure, supportive, and comfortable closure system that anchors the foot to that spot. So maybe, in assessing efficiency, we’ve been focused on the wrong part of the shoe. According to Hurt, future research could essentially flip the context: test shoes with an identical sole and different uppers to see if there are performance differences.
Securely and comfortably anchoring your foot to the pedal is easier said than done. The shoe is the interface between the dynamic structure of the human foot—with its 26 bones and dozens of muscles, ligaments, and tendons—and a fixed, mechanical power transfer system (the pedal and crankarm). Two components that factor heavily in that task are the upper materials and design, and the closure system.
Uppers can be relatively stiff or more flexible, and riders have personal preferences. But broadly, Curran says that what works best is an upper that is supple and flexible on top and offers progressively more support and structure toward the base, where it meets the sole plate, to keep your foot from slopping around. The pricier the shoe, the bigger the library of materials designers can access to create zoned support without extra bulk. Higher cost also affords more expensive construction techniques, like one-piece patterns and low-profile thermal bonding, instead of glued seams and stitches that might chafe.
Next: closure systems. They come in several different styles, including laces, hook-and-loop straps, buckles, and dial systems (Boa is the most popular). Shoes can feature more than one kind of closure. The two most popular systems are dial and lace closures, the latter of which came back into vogue partly for style reasons. But, said Sult, a few of the pro riders she works with prefer laces for functional reasons too. “They’re guys who don’t fiddle with their shoes during a race,” she said. “They know how tight they want the shoe, and then they don’t think about it again. Most athletes are constantly reaching down [to adjust closures].” For those folks, dial systems are the way to go. They’re more adjustable, lighter, and less bulky than buckles, which reduces pressure that creates hot spots. They have better mechanical holding power than any other system, and don’t stretch with use like straps. The intuitive rotary dials make it easy to crank a few clicks tighter on the midfoot closure for climbs or sprints, or looser on hot days when your feet swell. We like double-dial systems best because they allow you to adjust different zones on the foot, and thus fine-tune fit.
To the extent stiffness does matter, shoe manufacturers understand that we may be at a functional limit. Even Specialized’s new S-Works Ares, a shoe designed for sprinters, uses the same sole as the regular S-Works 7, which itself isn’t materially stiffer than the S-Works 6. “A lot of the work on that sole was to take weight out and still maintain power,” says Sult.
Very stiff soles also have an undesirable effect that’s easy to miss when shopping: just as a bike frame built for stiffness can be efficient but have a harsh, unpleasant feel, an overly stiff sole for a multi-hour training ride can be “like riding in a car with no shocks,” says Curran. But there can be a place for those shoes. A crit racer may want the stiffest shoe she can find, just for the powerful, connected feel of that rigid sole, and can accept a harsh ride because crits are short. But to Curran’s point, a rider interested in all-day comfort might be better served with a less-stiff sole, because it’s more comfortable for big rides, with no real compromise in efficiency (provided you have a good upper and closure system).
The Sweet Spot
So where do you get the best bang for the buck? In our view, right around $225. Road shoes are a highly competitive market, and common price points are around $100, $150, and $225. Above that, $300 is the next big stop, then $400.
At $225, you’ll get a reasonably stiff carbon fiber composite sole, an upper made of quality materials in a supportive design that minimizes bulk or hot spots, and a closure system with two dials or a single dial and a forefoot strap. These shoes also come in a fairly wide size range and may have different fit options (like gender-specific or wide-lasted) that aren’t available on less-expensive shoes.
The Specialized Torch 3.0 ($225) comes in a big range of sizes, including half sizes from 38 to 47. The Giro Regime ($225) has five millimeters of fore-aft cleat adjustment. Shimano RC-7 ($225) offers both of those benefits, and also comes in a wide-last version.
One affordable outlier that meets most of those qualifications is the Bontrager Velocis ($180), which comes in men’s and women’s specific versions, and offers five millimeters of fore-aft cleat adjustment. It has a single Boa closure with a forefoot strap, which differentiates it from the dual-dial systems on the three shoes above.
Above and Below the Sweet Spot
When you drop to $150, you’ll typically get a nylon-glass fiber outsole. It will likely be close in longitudinal stiffness to the $225 shoe from the same brand, but torsional stiffness may be lacking, which can lead to fatigue or foot pain on long days. Shoes in this price point have uppers made of less supple materials throughout, and single-dial closure systems or some other setup instead of a double-dial closure.
However, there is one specific reason to look at more affordable shoes. Most road pedals use a cleat with a three-bolt attachment system. But some riders prefer double-sided pedals that use a two-bolt cleat, like Shimano’s SPD mountain bike system. Shoes at the $100 and $150 level are typically compatible with that cleat pattern, while higher-price shoes are not. A great candidate is Pearl Izumi’s $160 Attack.
Above $225, you’ll get more comfortable uppers without stitches and seams that can irritate your feet, and more sophisticated two- and even three-zone closures, as well as those full-carbon outsoles. But except for specific purposes, those may not add a lot of performance. (One exception: if you constantly suffer hot feet, the lighter, better-ventilated uppers found on premium shoes may be worthwhile. And those with especially wide or narrow feet, or issues like bunions or neuromas, may find pricier shoes from specific brands work best for them, because those shoes come in more size options and lasts.)
Expensive shoes also tend to be slightly lighter, the high-quality uppers feature almost no break-in time and may last longer, and they’re often a little more comfortable. If you value a high-end shoe, there’s little downside except paying more. But as with a lot of things in cycling, a $425 shoe isn’t anywhere near twice as good as a $225 model.
Lead Photo: torwai/iStock