PowerCranks help you achieve a smooth, even power stroke by separating the pedalling action of each leg, but we didn’t ﬁnd the claimed gains in ﬁtness and power. They work like conventional cranks, but independently of each other, by means of a friction clutch installed where each crank attaches to the bottom bracket axle.
Power produced on the down stroke from one leg can’t lift the other limb, as is usually the case, so it’s your muscle power that raises your leg to the top of the stroke. This stops you simply ‘stomping’ on the pedals, instead forcing you to work under-used muscles to move them through 360 degrees.
PowerCranks claim that three months’ training on these cranks will signiﬁcantly improve sustainable power and VO2 max by increasing pedalling efﬁciency. The increased demand on hamstrings, hip ﬂexors and core muscles means initial training rides of just 15 minutes are extremely hard, but you should return to full training volume within a month.
Even after this short time our core strength showed this was by far the best cycling-speciﬁc core training we’ve experienced. Long-standing muscle imbalances also improved. This helped make low-cadence climbing more ﬂuid, which should reduce injury and back pain.
But while these improvements are helpful, they don’t necessarily make you go faster. Our gains in sustainable power – the ability to work harder for longer – over three months haven’t been signiﬁcantly different compared with previous seasons, which ties in with general scientiﬁc thought that big gains are unlikely under normal riding conditions.
On the Dual-Mode version the cranks can be locked so they work together and can be adapted for a wide range of training sessions. Crank length can also be adjusted between 145mm and 182.5mm simply by moving serrated inserts holding the pedal threads.
The injury prone or those facing a slow grind up Pyrenean or Alpine cols should consider PowerCranks, though they weigh 1,700g without chainrings. They’re only compatible with square taper, ISIS or Shimano Octalink splined axles, so you might need to budget for a new bottom bracket as well.