They often feel better before they are ready

A hamstring strain can happen in one moment. You might feel a sudden pull during football, netball, soccer, sprint training, tennis, running hills or kicking. Sometimes you can keep going for a few minutes, then later notice pain walking, bending forward, getting in and out of the car, or taking longer strides.

For other people, hamstring pain builds more slowly. It might sit high near the lower buttock, feel worse with sitting, or flare when you increase running, gym work, deadlifts or hill sprints. This is more consistent with hamstring tendinopathy, which needs a slightly different approach to a fresh muscle tear.

The tricky part is that hamstrings often settle with rest, but rest alone does not prepare the tissue for sprinting, cutting, kicking or repeated accelerations. A good rehab plan helps you build confidence as well as strength, so you know what to keep doing, what to modify, and when it is safer to progress.

Hamstring Force in Running Vs Sprinting

Most people do not realise how much harder the hamstring works when sprinting compared to running. The table below, adapted from a biomechanical study by Dorn, Schache and Pandy, shows how peak hamstring force increases as running speed increases.

Running Speed	Force x body weight
Jogging	2.6 x body weight
Running fast	4.6 x body weight
Sprinting	9 x body weight

This demonstrates how important good rehab plans, return to sport testing and graded sprint progressions are for safe return to activity.

How does physio help with hamstring injuries?

Physio will help with hamstring strains, muscle tears and hamstring tendinopathy by assessing the injury, reducing early aggravation, restoring strength and guiding your return to running or sport.

For an acute hamstring tear, we look at the likely grade of strain, your walking, range of movement, strength, bruising, sport demands and how soon you need to return. For ongoing tendon pain, we look more closely at sitting tolerance, hip strength, running load, gym programming and how your hamstring responds to compression and loading.

Hamstring injuries also have a high recurrence risk, especially when athletes return before strength, sprint exposure and sport-specific capacity have been rebuilt. That is why we usually recommend being assessed early rather than guessing your way back through random stretches or a few easy jogs.

Basic hamstring anatomy

Your hamstrings are a group of three main muscles at the back of the thigh:

• Biceps femoris, which sits more toward the outside of the back thigh
• Semitendinosus, which sits more centrally/inside
• Semimembranosus, which sits deeper on the inside
• These muscles attach near the sitting bone at the pelvis and cross the back of the knee
• They help extend the hip, bend the knee and control the leg during walking, running and kicking
• They work especially hard during high-speed running, when they help control the lower leg as it swings forward before your foot hits the ground

A hamstring tear usually involves the muscle or the muscle-tendon junction. Tendinopathy usually involves the tendon, often high near the sitting bone. Both can cause pain in the back of the thigh, but they are managed differently.

Common symptoms

You may notice:

• A sudden sharp pull, grab or pop in the back of the thigh during sprinting, kicking or changing direction
• Pain walking, especially with a longer stride or faster pace
• Bruising, swelling or tenderness in the back of the thigh after a more significant tear
• Weakness when bending the knee, pushing off, running or climbing stairs
• Tightness that keeps returning when you increase speed or training load
• Pain high near the lower buttock, especially with sitting, hill running or deadlifts, which may suggest hamstring tendinopathy
• Reduced confidence accelerating, sprinting, stretching out for a ball or returning to sport

What can contribute to hamstring injuries?

There often isn’t one single cause. Hamstring injuries usually happen when the load placed on the hamstring is greater than its current capacity.

This can happen with:

• A sudden increase in sprinting, hills, kicking, gym work or training volume
• Fatigue late in training, games or repeated sprint sessions
• Previous hamstring injury, especially if rehab was rushed or incomplete
• Strength or capacity differences between sides
• Limited tolerance to high-speed running or longer-stride positions
• Poorly timed return to sport after a break, holiday, illness or preseason ramp-up
• Technique, workload, recovery, sleep and stress factors that affect how well the body handles training

Walking and sprinting are not the same demand. You might be able to walk pain-free quite early, but sprinting exposes the hamstrings to much higher force, speed and stretch demands. That is why “it feels okay walking” is not enough to know your hamstring is ready for sport.

Hamstring strain severity

Hamstring strains are often described in grades. These are useful, but they are not perfect. Your actual return depends on your symptoms, strength, sport, previous injury history and whether you can meet progression criteria.

Hamstring strain level	What it usually means	Typical return-to-sport timeframe
Grade 1: mild strain	Small amount of muscle fibre irritation or tearing. Walking may be okay, but sprinting feels painful or unsafe.	Often around 1–3 weeks, depending on symptoms and sport demands.
Grade 2: moderate tear	Partial tear with more pain, weakness, movement restriction and possible bruising. Running is usually limited early.	Often around 3–8+ weeks, sometimes longer for higher-speed sports.
Grade 3: severe tear or rupture	Major tear, marked weakness, significant bruising, difficulty walking, or possible tendon involvement/avulsion.	Often several months and may require specialist opinion, especially if tendon avulsion is suspected.

These timeframes are general guides, not clearance rules. A safer return to sport is usually based on meeting strength, running, sprinting and sport-specific criteria, not just waiting a certain number of weeks.

Hamstring tendinopathy

Hamstring tendinopathy is different from an acute muscle tear. It often causes pain high at the back of the thigh near the lower buttock or sitting bone. It may feel worse with sitting, driving, running hills, faster running, deep lunges, Romanian deadlifts or stretching.

Treatment usually focuses less on stretching and more on:

• Reducing the most irritating loads for a period
• Building tendon capacity gradually
• Improving hip, glute and hamstring strength
• Adjusting running, gym and sport volume
• Progressing back to speed, hills and heavier strength work at the right pace

We still assess the whole person, because tendon pain can be influenced by training load, recovery, strength, movement patterns and previous injury.

How we assess hamstring injuries

In your first session, we’ll look at:

• How the injury happened and what you felt at the time
• Walking, stride length, bruising, swelling and tenderness
• Hip and knee range of movement
• Hamstring strength in different positions
• Running, gym, work or sport demands
• Previous hamstring, calf, back, hip or groin issues
• Your goals, timeline and what you need to return to

We will also discuss whether imaging or medical review may be useful. Many hamstring strains can be managed clinically, but imaging may be considered for more severe injuries, significant bruising, major weakness, suspected tendon avulsion, or when symptoms are not following the expected pattern.

How we treat hamstring injuries

Depending on what we find, your treatment plan may include:

• Hands-on physio to help settle pain, improve movement and guide early recovery
• Education and advice on what to avoid, what to keep doing and how to protect the injury early
• Exercise rehab to restore hamstring strength, control and confidence
• Strength and conditioning using our onsite rehab gym when appropriate
• Load management for running, gym, work and sport
• Return-to-running and sprint progressions
• Return-to-sport or return-to-gym planning based on your actual demands

Early rehab may start with simple pain-guided movements and isometric strength work. As symptoms settle, we usually progress into heavier strength, eccentric loading, running mechanics, acceleration exposure and sport-specific drills. For field and court sport athletes, the final stage needs to include speed and change-of-direction demands, not just slow gym exercises.

Return to sport: what we look for

We use a staged approach rather than relying on time alone. ASPETAR’s hamstring rehabilitation pathway is often used in sports medicine as a guide because it emphasises criteria-based progression, not just “rest until it feels better”.

Before returning to full sport, we usually want to see:

• Pain-free or near pain-free daily movement
• Full range of motion
• Good hamstring strength compared with the other side
• Passing multiple in clinic return to sport tests (specific to your sport)
• Symmetry to your other leg in movements like hopping and jumping using our Axit Force Plates
• Tolerance to faster running and progressive sprint exposure
• Confidence with acceleration, deceleration and sport-specific movements
• No sharp pain, guarding or major next-day flare after training
• A plan for ongoing strength and sprint-load maintenance

For football, soccer, netball, rugby, running and court sports, this matters because hamstring injuries often recur after return to play. A clear rehab and return-to-sport plan can help reduce the chance of rushing the last stage, which is often where people get caught.

Why choose Fitness Physio?

Fitness Physio helps people in Newcastle and Merewether recover from muscle, tendon and sports injuries with practical assessment and evidence-based rehab.

For hamstring injuries, our strengths include:

• Clear first-session assessment and explanation
• Hands-on physio when it is useful for pain and movement
• Exercise rehab and strength progressions
• Onsite rehab gym for stronger later-stage rehab
• Experience with running, gym, field sport and return-to-work demands
• Practical return-to-sport planning rather than generic rest advice
• High level accurate data to ensure you’re ready to get back to sport

The aim is not just to get your hamstring feeling better. It is to help you return with a plan, confidence and a better understanding of how to manage future training loads.

Book a hamstring injury assessment in Newcastle or Merewether

If you have pulled your hamstring, felt a sudden tear while sprinting, or keep getting recurring tightness when you return to sport, book an Initial Physio Assessment at Fitness Physio.

We’ll assess the injury, explain what may be contributing, and help you build a clear plan for walking, running, gym, work and sport.