Hamstring muscle strain is one of the most common injuries in sports that involve high-speed running, jumping, kicking and rapid change in direction of movement using the lower limbs. For instance, in British soccer, hamstring strains make up 12% of all injuries, meaning there is an average of five injuries per club per season. This means on average, three to four matches are missed due to the injury. Hamstring strain has one of the highest recurrence rates of up to 12%. The good news is that hamstring injury can be prevented with a proper warm-up drill, if you haven’t seen our Instagram post on FIFA 11+ go check it out!
This blog will focus on what is hamstring muscle strain, the two different types, the time-period taken before return to play (RTP), and what the rehabilitation process looks like.
Mechanism of injury behind the two types of hamstring injury
There are two types of acute hamstring muscle strains, type I and type II.
Type I occurs during high-speed running. Think about a football player sprinting at full speed but then needing to quickly change the direction of movement. Hamstring is the most vulnerable near the terminal swing phase in a sprint where the muscle must work eccentrically (contracting whilst lengthening at the same time) to decelerate the swinging tibia (shin bone) and control the knee extension in preparation for foot strike /placement. Involved structure: commonly long head of bicep femoris, proximal muscle-tendon junction.
Type II occurs during ballistic or large amplitude of movements leading to extensive lengthening of the hamstrings when in more hip flexion, think of it like a gymnast performing a high kick or a football player going for a slide tackle. Involved structure: proximal tendon of semimembranosus located close to the ischial tuberosity (your sitting bone).
The history of injury tells you a lot about which type of hamstring strain it is. There are some tell-tale signs and symptoms of how to tell if you have got an acute hamstring muscle strain.
moderate to severe pain intensity
difficulty walking, inability to run
flexibility markedly reduced
pain against resistance
visible signs of local bruising and hematoma
focal tenderness in one location.
Prognosis and Return to Play
There are a few predictors that are consistent with increased length of time to RTP. The prognosis becomes quite important in managing athletes’ expectations with RTP as unrealistic information only reinforces the disappointment and frustration of the injured athletes.
Type II – a “kicking” or “slow-stretching” mechanism of injury involving the proximal tendon of the semimembranosus; the closer the injured site is to the ischial tuberosity the longer it takes
Length of tear more than >55% cross-sectional area
Days to walk at a normal pace pain-free
>1 day = > 3 weeks to RTP
Days to jog pain-free
1-2 days = <2 weeks to RTP
3-5 days = >2 weeks to RTP
>5 days = >4 weeks to RTP
We will go through in detail of how rehabilitation process usually goes, from acute phase to subacute and RTP (sports).
Step 1. Acute phase
The first stage of recovery in which pain and swelling are prominent during the first few days following the injury. This is a good time to apply PEACE & LOVE principles we mentioned in our previous blog on “Ankle Sprain Rehab for Football players”. Here is a reminder of what those acronyms stand for:
Protection – avoid aggravating factors for 3 days but don’t stop moving
Elevation – elevate the limb higher than the heart to promote interstitial fluid flow out of tissue
Avoid anti-inflammatories – anti-inflammatories can potentially be detrimental for tissue healing
Compress – reduce swelling
Educate – benefits of active approach to recovery
Load – normal activities resumed as soon as symptoms allow
Optimism – will enhance the likelihood of an optimal recovery
Vascularisation – or angiogenesis allowing the formation of new blood vessels and myofiber regeneration
Exercise – low-grade pain-free muscle contraction promotes angiogenesis, helps to restore mobility/ strength/ proprioception early
The objective of acute phase management is to encourage myofiber regeneration and to reduce the chance of fibrosis, as minimizing scar formation reduces the chance of injury recurrence.
Early Exercises – e.g. active prone knee bends, single-leg hip extension
Once you can walk pain-free and exert adequate hamstring contraction against resistance, congratulations! You can now move on to the next phase.
Step 2. The subacute phase
The subacute or conditioning phase is where things start to get serious. Your rehab can be structured and designed by using periodization (as mentioned in our Ankle Sprain blog) where the macrocycle should consist of the following mesocycles:
Rate of force development (RFD = power)
Functional progression (sports-specific)
Before we head into the rehab block, let’s talk briefly about stretching and soft tissue treatment.
Stretching – should be considered on an individual basis. The main reason is that majority of injured athletes regain their normal range of motion without the need for excessive or aggressive hamstring stretching program. In fact, it may be more worthwhile to perform controlled stretches to other structures such as the hip flexor muscles that may be placing the hamstring at an increased risk of strain.
Soft tissue treatment – can be applied to the hamstring muscles to assist with scar reorganization.
Now that we know the outline structure of the rehab program, let’s focus on the first two mesocycles: strength and neuromuscular control.
Strength - Most hamstring strains occur when the muscle group is extensively lengthened, thus, the training program should include exercises emphasizing on eccentric muscle contractions and the ability to develop tension at speed. As the hamstring muscles span across not just one but across two joints (hip and knee), the program should also consider compound exercises.
Single-leg bridge catch
Single-leg ball rollouts
Single-leg standing hamstring catches with resistance band
Single-leg deadlifts with dumbbell
Machine hamstring curl in prone (facing down)
But don’t forget to include exercises to work on other muscle synergies such as the gluteal muscles. The main reason is the gluteal muscle group contributes up to 50% of isometric hip extension, therefore, inadequate strength can place the hamstring muscles in a vulnerable position of overload.
Neuromuscular – Just acquiring pure strength but not being able to control the positioning of body or the speed of movement the way you want it means a heightened risk for re-injury.
Single leg balance
Single-limb balance windmill
Step 3. Power and Sport-specific exercises
Finally, we can start to focus on a later stage of rehab which includes power and sports-specific running drills. A formal running program (3 runs a week) should commence once the athletes are comfortable running at 50% intensity.
Proper warm-up i.e. jogging prior to running then progress to agility drills
Implement intervals into the running program e.g. sprint 40m then constant pace for 20m then decelerate for 40m; add further challenge by adding in a change of direction or even back peddling
Add in sports-specific drills i.e. running with the ball uncontested / contested
Step 4. Return to Play
Before returning to sports or competition, the athletes will need to fulfill certain criteria to prevent the recurrence of injury. A criteria-based approach to rehabilitation will help identify deficits and address them accordingly.
Normal range of motion
Full power with contraction (pain-free)
Less than 5-10% of eccentric strength deficit between both sides
Tenderness with palpation equal on both sides
Successful completion of running program (i.e. accelerate 40m, constant speed 20m (in 2.5s), decelerate 20m; repeated 3 times
Successful completion of appropriate rehabilitation exercises
Successful completion of at least two normal-duration training sessions at maximal exertion
Although acute hamstring strain can be common and debilitating, the good news is that you can get better by following a well-structured plan and staying on top of it. If you have any questions about this blog, give our practice a call on 07 3061 7128 or send us an email firstname.lastname@example.org