Athletes and fitness enthusiasts are constantly pushing the limits of their bodies to achieve peak performance. This drive for excellence however comes with an inherent risk of injury, with the hamstring muscles being particularly vulnerable for many athletes participating in sports requiring high-speed running and kicking like football and soccer.
In this blog post, we will start by outlining the basic rehabilitation principles and then further explore some recommendations for the early phase of rehabilitation. Keep an eye out for future posts on the topic, where we will discuss in more detail the progression back to a safe return to sport and what you should be doing to reduce your risk of an injury recurrence.
Understanding Hamstring Injuries
The hamstring muscles, located at the back of the thigh, consist of three primary muscles: the biceps femoris, semitendinosus, and semimembranosus. These muscles play a vital role in activities involving leg movement, such as running, jumping, and kicking. Unfortunately, they are also susceptible to injury due to their involvement in high-intensity movements, especially high speed running.
Hamstring injuries are generally categorised into three grades:
Grade 1: Mild strain with minimal fiber damage and discomfort.
Grade 2: Moderate strain with partial tearing of muscle fibers, resulting in pain, weakness, and limited mobility.
Grade 3: Severe strain or complete tear, causing intense pain, significant loss of function, and difficulty walking or bearing weight
It's also worth mentioning that subcategories exist within these grades which are likely to influence return to play times and re-injury risk. This can be useful in individuals participating at a high level of sport where it's critical to minimise games or events missed due to injury. These subtleties can be identified with an MRI scan, and with this information at hand, your sports physio can adjust your rehab program accordingly.
Key Rehabilitation Stages:
Sports physiotherapy plays an instrumental role in the recovery process of hamstring injuries, guiding you through each important phase of rehab to safely return you to your sport or activity. The following principles are critical to your rehabilitation success:
Early Injury Management: The initial phase after a hamstring injury requires prompt action to minimise pain, swelling, and further damage. Rest from any physical activity which places excessive strain on the hamstring is needed to protect the injured muscle and allow the early healing process to occur. Early resistance training under the guidance of your sports physio targeting the injured muscle is also usually beneficial as it may lead to earlier recovery of muscle function.
Restoring Muscle Capacity & Low Speed Running: As pain subsides and function starts to return, an appropriately structured rehabilitation program targeted at facilitating the full restoration of the injured muscle's capacity is needed. This program should also include a graded progression of running. This often starts with lower speed running before progressing to the next phase of rehab.
High Speed Running & Agility Drills: High speed running can commence once adequate strength and capacity in the injured hamstring has been restored. Speeds will gradually increase, agility drills can be introduced if required by your sport and there should be repeated graded exposure to the original injury mechanism (if different from sprinting- e.g. kicking).
Return to Training & Competition: Following a solid block training involving high speed running, agility (if required), and exposure to the original injury mechanism, athletes should be introduced to high intensity sports/activity-specific drills before returning to unrestricted competition.
Prevention Strategies: Hamstring injuries are often the result of errors in training load prescription and may also be contributed to by underlying biomechanical imbalances or faulty movement patterns. It's important to have a thorough assessment in each of these areas to identify any contributing factors. By addressing these factors you can reduce the risk of re-injury and optimise performance. Ensuring proper warm-up exercises, resisted exercises to maintain muscle strength and appropriate training loads can also help minimise the risk of hamstring injury recurrences.
With an understanding of the above stages of hamstring injury rehabilitation, lets now discuss in more detail the components of the first early rehabilitation phase. This will likely vary between individuals depending on their sport, the original injury mechanism and the severity of injury.
Early strengthening: it's usually safe to start your hamstring strengthening exercises quite early in your rehab journey. Lower grade strains can often start as early as one to two days post-injury! The type and intensity of the exercise will vary depending on each individual injury, however as a general rule, exposure to one knee dominant and one hip dominant hamstring exercise is important (the hamstrings cross both the hip and the knee joint, therefore they are used to generate movement at the hip and knee). An example of this would be a prone hamstring curl (knee dominant) and a hamstring bridge (hip dominant), both seen in the pictures below. Not only is early strengthening safe (when programmed appropriately), but it is also thought to result in an earlier recovery of your hamstring strength which could have implications on your return to play time and risk of re-injury.
Return to low speed running: Once you've restored adequate range of motion and strength in your hamstring, low speed running at a comfortable jogging pace can start. This can sometimes be as early as 2-3 days post-injury, but this will be dependant on your specific presentation and should guided by your physio. What constitutes adequate range of motion is debatable, however we believe if you've restored your hamstring length to within 10-15% of the non-injured side (your physio can test this!), this should be adequate.
Regarding your strength, being able to complete at least 10 single leg hamstring bridges (see pic above) through full range of motion is a good indication you have recovered enough strength for a light jog. Another useful test (although less accessible) is assessing your knee flexion torque. Your physio can measure directly the force output of the hamstring muscles using a device called a dynamometer. This force output is then converted to a standardised measure of newton-meters per kilogram of bodyweight (nm/kg) to account for the different bodyweight and limb lengths of each individual. From kinetic studies of running and sprinting, It's thought that low speed running demands less than 1 nm/km of knee flexor torque, therefore this is a good starting point.
Stage 2: Restoring Muscle Capacity & Training Loads
Working with your physio to determine when you're ready to start strength exercises and start running is a very important part of your rehab plan, as this can effect how long you spend on the sidelines and can also influence your risk of re-injury. Once you've ticked these boxes, the next phase of your rehab is all about restoring your hamstring muscle capacity to at least its pre-injury level through heavy resistance training and progressively increasing the intensity of your rehab running. Keep an eye out for our next blog post, where we will discuss in more detail how and why this is done.
For all your sports physiotherapy needs, remember to visit us at ProSport Physio, your trusted partner in injury prevention, rehabilitation, and performance enhancement. We are dedicated to helping individuals achieve their goals and overcome any hurdles along the way!