How Quadriceps Muscle Shape Can Influence Cycling Cadence and Torque

Cyclists with similar body weight, threshold power and muscle fibre composition can favor very different cadences. One may ride comfortably at 110 rpm in a fast group, while another prefers a heavier gear at 75 rpm on a climb. Muscle architecture offers one possible reason for that difference, though it’s only part of the picture.

Two features of the quadriceps help describe this architecture: fascicle length and pennation angle. They shape how muscle fibers are arranged and how they produce force. Neither measurement, by itself, dictates a cyclist’s ideal cadence. Training, technique and the demands of a ride also matter.

Two measurements, two mechanical effects

Sports scientists can use ultrasound to examine the vastus lateralis, one of the muscles in the quadriceps. They may measure the length of its fascicles and the angle at which muscle fibers attach to the tendon.

A fascicle is a bundle of muscle fibers. Its length reflects how many sarcomeres, the small units that produce force, are arranged in series. Longer fascicles can shorten more quickly, which may help a muscle produce force at higher shortening speeds.

Pennation describes the angle between muscle fibers and the tendon. The fibers don’t all pull straight along the tendon; they meet it at an angle. A larger pennation angle lets more fibers fit within a given muscle volume, which can support greater force production. At high contraction speeds, though, a smaller share of that force is directed along the tendon’s line of action.

These traits describe different advantages rather than a simple ranking. Longer fascicles are associated with greater shortening velocity, while a larger pennation angle can support a higher concentration of force-producing fibers. How those features play out on the bike depends on the rider and the effort.

Cadence and torque preferences

A rider with longer fascicles and a smaller pennation angle may be better suited to rapid contractions. That profile can support high-cadence riding, including efforts around 100–120 rpm, and quick responses to surges. It may also make fast pedaling feel more natural over sustained efforts.

By contrast, shorter fascicles and a steeper pennation angle can support high force at lower contraction speeds. That combination may suit a rider who prefers pushing a larger gear at 60–80 rpm, especially on steep gradients where each pedal stroke must deliver substantial torque.

These are tendencies, not rules for assigning riders to a single style. A preferred cadence is shaped by more than quadriceps geometry, and the cadence that works in a short hard effort may not be the most comfortable choice for a long ride. The useful question is how a rider produces power and manages effort across the terrain at hand.

Training can affect muscle architecture

Muscle geometry was once treated as a fixed trait, but research indicates it can change with training. Blazevich and colleagues’ 2007 research found measurable changes in quadriceps architecture following specific resistance training. Eccentric loading, in which a muscle lengthens while under tension, may encourage the addition of sarcomeres in series and increase fascicle length over time.

A 2014 review by Rønnestad and Mujika examined heavy resistance training for endurance cyclists, including exercises such as squats and leg presses. The authors reported changes in fascicle length and pennation angle in well-trained cyclists. Such training may improve force production and pedaling capacity without necessarily adding substantial muscle bulk or reducing aerobic capacity.

The practical point is that cycling performance doesn’t have to be limited by a rider’s starting muscle profile. Resistance work can be part of an endurance program, but the source findings describe training effects, not a guaranteed outcome for every cyclist. The demands of the program and the rider’s response still count.

Use cadence tests as clues, not diagnoses

Ultrasound is needed to measure fascicle length directly. A bike test can offer a rough comparison of how a rider performs at different cadences, but it can’t reveal muscle architecture on its own.

One suggested comparison uses two three-minute maximal efforts on a flat, quiet road or a smart trainer: one at 70 rpm in a heavy gear and another at 110 rpm in an easier gear, with full recovery between efforts. Compare the power produced and how sustainable each effort feels. A stronger result at 70 rpm may point to a preference for high-torque riding; a better or more sustainable effort at 110 rpm may suggest greater comfort at higher cadence.

Keep the limits of that comparison in view. Differences in pacing, fatigue and familiarity with each cadence can affect the result, so a single session can’t establish a rider’s muscle structure. Treat it as a prompt to explore cadence choices, not as a diagnosis or a prescribed training target.

There’s little reason to force a cadence above 100 rpm simply because elite riders use it. If fast spinning feels inefficient, a rider may spend more effort maintaining it without gaining a useful benefit for that session. Equally, a preference for low cadence doesn’t mean every climb should be ridden in the heaviest gear available. Match cadence to the effort and terrain, and build strength and technique progressively.

Muscle architecture helps explain why cyclists can produce power in different ways. The next question is how cadence changes the body’s effort at the same wattage, including the neuromuscular demands of riding at 60 rpm versus 100 rpm and the effect on glycogen use.

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