High‐load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12‐month follow‐up

The aim of this study was to investigate the effectiveness of shoe inserts and plantar fascia‐specific stretching vs shoe inserts and high‐load strength training in patients with plantar fasciitis. Forty‐eight patients with ultrasonography‐verified plantar fasciitis were randomized to shoe inserts and daily plantar‐specific stretching (the stretch group) or shoe inserts and high‐load progressive strength training (the strength group) performed every second day. High‐load strength training consisted of unilateral heel raises with a towel inserted under the toes. Primary outcome was the foot function index (FFI) at 3 months. Additional follow‐ups were performed at 1, 6, and 12 months. At the primary endpoint, at 3 months, the strength group had a FFI that was 29 points lower [95% confidence interval (CI): 6–52, P = 0.016] compared with the stretch group. At 1, 6, and 12 months, there were no differences between groups (P > 0.34). At 12 months, the FFI was 22 points (95% CI: 9–36) in the strength group and 16 points (95% CI: 0–32) in the stretch group. There were no differences in any of the secondary outcomes. A simple progressive exercise protocol, performed every second day, resulted in superior self‐reported outcome after 3 months compared with plantar‐specific stretching. High‐load strength training may aid in a quicker reduction in pain and improvements in function.