If you regularly ride your bike or take an indoor cycling class, consider trading in your running kicks for a pair made specifically for cycling. Cycling in running shoes prevents you from creating maximum power with every pedal stroke. It can also lead to discomfort and may result in muscle imbalances. Investing in clipless shoes, special biking shoes that affix to your pedals, can help you get the most out of your workout.
Running shoes have a flexible bottom, which may bend and irritate your foot with each pedal stroke. You may even experience cramping and numbness because of this. Cycling shoes that snap into the pedals have a stiff bottom which prevents this discomfort. Running shoes are also more likely to slip off the pedals, which means you could get slammed in the shin by the crank or lose control, especially if you're outside.
Cycling shoes that clip into the pedals enable you to use the entire pedal stroke so you not only work your quadriceps as you push down, but your hamstrings and glutes as you pull up. Running shoes won't "clip" into the pedals, so you may overwork your quadriceps because you'll rely on the pushing action to generate power. Even if you use a "cage," which consists of several straps that hold your foot onto the pedal, with running shoes, you won't get the same control that you do with clipless cycling shoes and your quads will risk over development.
Cycling shoes evenly distribute your weight over your pedals and enable you to use more muscles for every pedal stroke, meaning you'll have more power. When you wear running shoes to cycle, you lose this power and experience a less-effective, less efficient ride. If you cycle outdoors for miles at a time, you want your feet to stay cool. Cycling shoes come with special vents that maximize air flow while running shoes do not.
What's a Runner to Do?
If you are a runner who cross trains with cycling regularly -- say once or twice per week, or even per month -- it's time to invest in a pair of cycling shoes. Your running shoes will rest and you'll get a better cross-training experience on the bike. But, if your bike collects dust in the garage and you only pull it out once or twice per year, you can get by with your running shoes.