Carbon Fiber Insoles vs Super Shoes: What the Research Actually Shows

# What carbon fiber insoles are Carbon fiber insoles are thin carbon plates designed to replace your shoe's liner. They stiffen the forefoot and mimic the carbon plate in a super shoe, but they do not change the midsole foam or the shoe's rocker geometry.

# What a plate actually does When you push off, toe-base joints bend and absorb energy. A carbon plate limits that bending, so less energy is lost. Studies measuring running economy show that a plate can reduce the energy cost of running by a few percent for some runners. One study in Medicine and Science in Sports and Exercise found a carbon plate reduced energy cost by up to 3.8% and improved a 3000 m time trial by about 5 seconds for trained club-level runners.

# Why a carbon insole won't fully match a super shoe

# What details change the effect

• Plate shape: a 2022 analysis of 12 studies found curved carbon plates improved running economy by about 3.45%, while flat plates produced no improvement.
• Weight: added mass blunts the benefit. The same analysis showed the effect shrank when the stiff shoe weighed roughly 35 g more than the flexible version. To avoid this, remove the stock liner and use the carbon insole in its place so you replace weight rather than add it.

# Who is most likely to benefit Trained runners show measurable benefits at a range of paces. The club-level runners in the 3.8% study (10K times 38–45 minutes) gained across both easy and fast paces. National-level runners in the same study gained only at their fastest tested pace. Group-level responses vary: in the largest study roughly 30% of runners used less energy with a stiffer forefoot while about 27% used more.

# Practical guidance for using carbon insoles

• Cost and fit: carbon insoles typically cost $95–$149 and fit any shoe with a removable liner. A new pair of super shoes costs around $250–$280.
• When to use them: reserve them for faster workouts (tempos, intervals) where the plate can help your economy. Many coaches still recommend standard trainers for most training and saving super shoes for racing.
• How to install: remove your shoe's stock liner and install the carbon insole so you replace weight instead of adding it.
• Break-in and injury risk: build them in over 3–4 weeks to avoid overloading calves and the Achilles. Start with short sessions and increase volume gradually.
• How to test whether they help you: run a fixed-pace effort and compare heart rate (or perceived effort) between your regular liner and the carbon insole. If heart rate is lower at the same pace with the insole, you're probably responding positively.

# Bottom line