❓What Is a Muscle Strain?

A muscle strain happens when a muscle is rapidly stretched and partially tears during physical activity.
It most commonly affects the hamstrings (back of the thigh) and the calf muscles (gastrocnemius).
It tends to occur during eccentric contractions — when the muscle is lengthening while producing force — such as during sprinting or landing from a jump.

⚙️Why Does It Happen?

1

The muscle is in poor condition

Lack of flexibility, accumulated fatigue, or insufficient warm-up combine

2

A sudden powerful movement occurs

Sprinting or jumping stretches the muscle while applying strong force

3

Muscle fibers tear

The fibers rupture partially beyond their limit, causing internal bleeding

🧘 Poor Flexibility 😰 Muscle Fatigue 🏃 Insufficient Warm-up 💧 Dehydration 🔄 Previous Strain History

🔍Watch for These Symptoms

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A sudden "pop" or tearing sensation

🎈

Swelling at the injured area

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Bruising (internal bleeding) spreading

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Pain when walking or inability to bear weight

💊Treatment

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Initial Care

RICE (Rest, Ice, Compression, Elevation) for roughly the first 24–48 hours. More recent approaches such as POLICE and PEACE & LOVE favor protected early movement within the limits of pain. Do not judge how much to move on your own — follow your doctor's instructions

🧘

Gradual Rehabilitation

Progress from stretching → light strengthening → sport-specific drills

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PRP Therapy

Uses growth factors from your own platelets to promote tissue repair. Some randomized trials found no shortening of return-to-play time, so its value is not yet settled. For muscle strains it is not covered by insurance (self-pay)

⚡

Shockwave Therapy

Sometimes used in stubborn or recurrent cases hoping to reduce pain and support repair. Evidence for its effectiveness in muscle strains is limited, and it is not covered by insurance (self-pay, 3,000 yen incl. tax per session)

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MRI / Ultrasound

Imaging to accurately assess the extent and severity of the injury

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Return-to-Play Decision

Follow-up MRI confirms full healing before returning to competition

📈Outlook & Recovery

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Recovery time depends on severity

Mild strains (Grade I) may heal in 1–2 weeks, moderate (Grade II) average around 5 weeks (ranging from 2 to 10 weeks depending on the extent of damage), and severe (Grade III) take 3 months or more, sometimes close to six months in the worst cases. Returning too early greatly increases the risk of re-injury, so a gradual, step-by-step approach is important.

🏃For Athletes & Active People

Muscle Strain

Recovery time depends on severity

💡 How to Prevent Re-Injury

🩻 Gotokuji Orthopedic Clinic