Hamstring injuries are extremely common in sports that involve sprinting, jumping, and sudden changes in direction. They account for a large percentage of all injuries in sports like football, soccer, basketball, and track & field. However, there are several things athletes can do to reduce their risk of hamstring strains and tears.
Hamstring Anatomy
The hamstrings are a group of three muscles located on the back of the thigh:
- Biceps femoris
- Semitendinosus
- Semimembranosus
These muscles work together to bend the knee and extend the hip. They are particularly active during the late swing phase of running, working eccentrically to decelerate the leg before foot strike.
The biceps femoris sits on the outside of the back of the thigh. The semitendinosus and semimembranosus sit on the inside of the thigh. Studies show the biceps femoris is injured in over 75% of hamstring strains.
Mechanisms of Injury
There are two main types of hamstring strains:
Type I – Occurs during sprinting. Affects the biceps femoris when the muscle is eccentrically contracting while lengthened.
Type II – Occurs during slower movements like bending or lunging that excessively stretch the muscle. Affects the semimembranosus.
Both happen when sudden force is applied while the muscle is lengthened. This often occurs during the late swing phase of sprinting or rapid changes of direction.
Risk Factors
Some of the main risk factors for hamstring injuries include:
- Previous hamstring injury
- Muscle imbalances and weakness
- Poor flexibility
- Fatigue
- Improper warm-up
- Sudden increases in training load
- Older age
- Ignoring signs of tightness or soreness
Re-injury rates are very high, reported between 16-25% in elite athletes. Hamstring strains account for an average of 20 missed games per AFL season.
Prevention Strategies
Here are some tips to help reduce hamstring injury risk:
Perform Eccentric Strengthening
- Do eccentric exercises like Nordic curls which target hamstring strength while lengthened.
- Follow a progressive program over 10+ weeks.
Improve Flexibility
- Stretch hamstrings regularly using hurdle stretches, forward folds, and other static stretches held for 30-60 seconds.
- Use foam rollers and massage tools to relieve muscle tightness.
Strengthen Muscles
- Do hamstring curls, glute bridges, deadlifts, and other concentric/eccentric exercises.
- Strengthen glutes and core to reduce hamstring strain.
Warm Up and Recover Properly
- Do a thorough dynamic warm-up before activity.
- Allow enough recovery between intense sessions.
- Listen to warning signs like muscle tightness.
Use Proper Mechanics
- Increase stride rate and take shorter, quicker steps when running.
- Maintain upright posture and engage core during activity.
Wear Supportive Gear
- Use appropriate shoes with cushioning and support.
- Consider kinesiology tape or compression wear if at high risk.
Following prevention guidelines like these can significantly reduce hamstring strains. But if an injury occurs, stop activity immediately and seek prompt medical help. With rest, rehab exercises, and a gradual return to activity, most hamstring strains heal fully within 6-8 weeks.
