Stress fracture are two words no runner wants to hear. Whether you are a young track star or just enjoy a slow jog to decompress after work, a stress fracture can sideline you for several months. In any given year, more than one in five runners will suffer from a stress fracture. In this blog, we will discuss prevention strategies to keep you on pace!
The most common bone for runners to develop a stress fracture in is the tibia also known as the shin bone. The small bones in your feet (metatarsals), the fibula (thin bone in your outer lower leg) and your femur (thigh bone) are also common places to develop stress fractures. A stress fracture is a small crack in an otherwise normal bone. It is an overuse injury, developed from the repetitive action and forces in running. Stress fractures usually occur when the capacity of the bone to absorb impact is simply overloaded.
Muscle strength plays an important role in the prevention of stress fractures. Dr. Matthew Oliver, an orthopedic surgeon explains “stress fractures occur when muscles become fatigued and are unable to absorb added shock. Eventually, the fatigued muscle transfers the overload of stress to the bone, causing a tiny crack called a stress fracture.” An interesting research study looked at calf muscle size and the development of stress fractures. A 10-mm reduction in calf circumference resulted in a fourfold increase in tibial stress fractures. The calf muscles dampen the vibration to the bones that is caused when your foot strikes the ground during running. As you can see, adding in strength training for the legs can be a vital part of a runners training program.
Muscles in the legs also create a compressive force around the bones to resist bending strains as a runner is pounding the pavement. Remember one of the most common areas for a stress fracture is the metatarsals or small bones of the feet. The muscles that curl your toes create a stabilizing force around the bones in your feet that greatly reduce the strain placed on the bones. Strengthening these muscles in your feet may prevent metatarsal stress fractures.
A fascinating study compared the size and strength of leg bones of college soccer players and college cross country runners. The shin bone of the soccer players was 7.5% larger and 29% more resistant to bending forces. The soccer players also had enhanced structure and strength in their fibulas and metatarsals. The researchers concluded the improved bone strength was due to the fact that soccer players move in multiple different directions. While runners repetitively do the same motion of moving forward in a straight path. The research in this study indicates that young athletes should delay specialization in running and we should encourage children to participate in sports like soccer where they move in multiple different directions during a game and practice.
Another thing to think about for runners is incorporating moving in different directions into their warm-up and cool-down. For example, adding jogging backwards, shuffling sidewards, a zig zag run on the football field and karaoke crossover drills would allow a runner to move in multiple directions. Multi-planar lunges are great for strengthening as well as a way to move the leg bones forward, to the side and backwards. These movements would place a stress on the muscles and bones that improve the bone structure and help decrease the risk of developing a stress fracture.
No runner wants to be sidelined by a stress fracture. Adding in strength training and multi-directional movements can help prevent stress fractures. It is also important for young athletes not to specialize in running at a young age. Parents and coaches should encourage children to continue playing different sports to help improve the structure and strength of their bones. To keep on track striving for that runner’s high, have some fun moving in all directions with shuffles, karaoke drills, zig-zag runs, jogging backwards and multi-planar lunges.
References:
1. Sventeckis A, Et Al. Cross-sectional size, shape and estimated strength of the tibia, fibula and second metatarsal in female collegiate-level cross-country runners and soccer players. Bone, 2024
2. Michaud, Tom. Strength and Stress Fractures. Human Locomotion
3. Carter, Kate. Everything you need to know about stress fractures: The cause, healing time and how to avoid them. Runner’s World, 2024
