Adam Gemili’s Tokyo Olympics ended in heartbreak as the 27-year-old British Sprinter had to pull out of the 200-meter after suffering a hamstring injury moments before his heat. Gemili was hoping a podium finish at the ongoing centennial event after missing out on a bronze medal at Rio 2016, but his hopes shattered in a dash. He was set to compete for GB in the men’s 4x100-meter relay heats, but that seemed unlikely due to this injury.
Great Britain’s world champion Dina Asher-Smith suffered the same fate as she has pulled out of the Olympic 200-meter after a hamstring injury earlier at the British Olympic Trials. The 25-year-old also failed to make it to the final of the 100-m after clocking 11.05 seconds in the semi-final. But unlike Gemili, Dina Asher-Smith participated for GB in the women’s 4x100-meter relay and even set a new British record in the sprinting event.
Judging by the recent hamstring injuries of high-profile athletes in Tokyo, one might think of it as an innate injury hitting sprinters, regardless of how trained an athlete is. Often you’ll see a player with a hamstring injury with an expression of despair more than pain as an athlete regrets the feeling of disappointments and of the hard training just wasted. Take the case of Derek Redmond’s emotional Olympic story in Barcelona 1992 when he tore his hamstring in the 400-meters semi-final but finished a full lap limping with the assistance of his father. Hamstring injuries happen to all – even to the once fastest Usain Bolt.
Mechanism of Injury:During sprinting, the hamstrings slow down the lower leg as it swings forward very quickly and prepares the leg for foot contact. It’s at this instance that the muscle receive a lot of stress at extreme lengths and commonly leads to injuries because the hamstrings are shortening as they contract, while the knee is extending very quickly and pulling on the muscles, creating an excessive muscle strain. An eccentric contraction is when a muscle contracts as it lengthens. At the foot strike, the hamstrings absorb all the forces that comes with sprinting, which the muscles are unable to handle and so results in hamstrings strain.
At the hip, these muscles generate a great amount of force as they extend the hip backwards and help with the forward propulsion. Injuries can also happen at this situation because the muscles are generating tremendous amounts of force to maintain, or increase, forward running velocity.
Understanding individual risk factors for hamstring injury is vital to developing a prevention program. While age and previous hamstring injury are commonly identified risks, both are non-modifiable. Some common the modifiable factors include:
Research suggests that the most significant predictor of hamstring injury is a history of previous strain to the muscle.To prevent injuries, trainers, coaches, and therapists should always investigate these potential risk factors and once identified, they should be address and fix with appropriate treatment/preventive remedies.
Evidence shows that there are ways to prevent hamstring injuries and re-injuries.
Stretching before an athletic event or training ensures that an athlete has adequate flexibility to decrease muscle stiffness and perform optimally with decreased risk of injury. Dynamic stretching has been considered to be an effective method of preventing hamstring strain and should be incorporated in warm-up routines and should be running-specific. SeeReference.
As the hamstring muscles are usually injured during eccentric contraction, training them at this type of contraction is logical. It has been well documented that eccentric training programs, such as the yo-yo curl or Nordic Hamstring Exercise (NHE), are effective in the prevention of hamstring strains. Increasing the hamstring strength eccentrically is achieved by lengthening the hamstring complex while it is loaded and contracting. See Reference.
In sprinting, the hamstrings are required to switch rapidly from eccentric to concentric contraction and, therefore, neuromuscular coordination is critical. Agility training is practiced to accustom to the rapid motion required in sprinting. SeeReference.
A progressive agility training combined with trunk stabilization exercises has shown to be more effective than isolated hamstring stretching and strengthening in preventing hamstring reinjury. See Reference.
Strength imbalance between the hamstrings and quadriceps is a known intrinsic risk factor for hamstring injuries. While flexibility exercises prior to training or athletic event are advised, stretching may reduce hamstrings strength, thus increasing the muscular imbalance between the hamstrings and quadriceps. A study suggests that a 5-minute localized vibration therapy used to increase muscle flexibility can effectively improve hamstring flexibility without affecting hamstring strength, while improving performance.
ADAM GIMILI Photograph: Christian Petersen/Getty Images
DINA ASHER-SMITH Photograph: BBC