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The Complete Guide
To Hamstring Injury
Additional Information

Hamstring Injury: The Complete Treatment Guide

Understand the injury. Treat the root cause. Heal quickly.

You don't have to suffer. You don't have to wait.
  • You can reduce the pain and swelling.
  • You can heal quickly.

All YOU simply need is the right treatment.


King Brand Healthcare Products is the manufacturer of FDA-registered Class II medical devices for the treatment of soft tissue injuries. This guide covers what a hamstring injury is, why it happens, and how to treat it correctly.

What This Guide Covers



What Is a Hamstring Injury?

A hamstring injury is a strain or tear of the hamstring muscles, which run along the back of the thigh from the hip to the knee. The hamstrings bend the knee and extend the hip. Hamstring injuries range from mild strains to complete tears. They are common in sports that involve sprinting, jumping, or sudden changes of direction.

Hamstring injuries have a high re-injury rate. This makes the King Brand protocol especially relevant: KB Tape prevents re-injury during activity, and BFST stimulates blood flow to heal the damaged muscle.



Symptoms of Hamstring Injury

The most common symptoms:

  • Sudden sharp pain in the back of the thigh during activity
  • Pain that worsens with stretching or bending the knee
  • Swelling and bruising in the back of the thigh
  • Weakness when bending the knee
  • Tenderness to touch
  • A popping or tearing sensation at the time of injury


Common Causes of Hamstring Injuries

  1. Sprinting and sudden acceleration.
  2. Sudden changes of direction.
  3. Tight or weak hamstrings.
  4. Muscle imbalances. Stronger quads than hamstrings.
  5. Insufficient warm-up.
  6. Previous hamstring injury. Re-injury risk is high.
  7. Ignored early warning pain.

See Hamstring Information for more detail.



The Correct Treatment Protocol

The King Brand treatment protocol for a hamstring injury uses three FDA-registered medical devices working together, each addressing a different part of the recovery problem:

  1. ColdCure -- treats pain, swelling, and inflammation. Used whenever there is pain or swelling, and immediately after any activity that aggravates the injury.
  2. KB Tape -- supports the injury and prevents re-injury. Worn between treatments as "armor for your injury".
  3. BFST (Blood Flow Stimulation Therapy) -- stimulates blood flow to the injured muscle to promote healing. Used once swelling and inflammation are gone.

The order matters. Cold first, because treating an inflamed injury with anything else is premature. Support throughout, because every re-injury resets the healing clock. Blood flow stimulation once the acute phase is controlled, because that is what actually heals the muscle.

For the full protocol details, see Hamstring Treatment.


Combination Therapy
Combination Therapy BFST® + ColdCure® + KB Tape™


Complete TreatmentBFST® for Rapid Healing
Relieve PainColdCure® for Pain & Swelling
Heal QuicklyKB Tape™ to Prevent Re-Injury

Combination Therapy means using ColdCure®, KB Support Tape™ and BFST® in combination by alternating treatments. Combination Therapy is much more effective than using just one product or the other. This is because you're getting the pain and swelling relief of ColdCure®, the healing benefits of BFST®, and the protection and re-injury prevention of KB Support Tape™, resulting in the absolute best treatment for your Hamstring Injury.


Step 1: Reduce Swelling and Inflammation


ColdCure is a registered Class II medical device that delivers cold compression therapy for pain, swelling, and inflammation associated with soft tissue injuries.

Cold and compression applied to an injury that is swollen, inflamed, or painful is extremely effective. ColdCure treatments are beneficial following injury until the pain, swelling, and inflammation are gone, and any time you experience symptomatic flare-ups.

Three technologies distinguish ColdCure wraps from drugstore ice packs:

  • RigiGel -- a gel formula that stays in place under pressure and molds to the shape of your leg even when frozen, delivering cold exactly where it is needed.
  • PerpaChill -- a cold capacity formula that holds significantly more cold per gram than standard pharmacy gel packs.
  • XC -- a temperature-balancing formula that moves cold within the pack to where the injury is absorbing it, so there are no warm spots over the injury.

Each ColdCure wrap comes with 3 gel packs (the Large Body Wrap comes with 2): use one in the wrap while the others recharge in the fridge or freezer. Switch to a freshly charged pack when the cold diminishes, typically after 20 minutes.


Step 2: Support and Protect the Injury


KB Support Tape is a registered Class I medical device with two functions: ongoing compression to control swelling, and support to protect against re-injury.

The support function is the important one for a hamstring injury recovery. When applied as an "X" or "T" with the crossover directly over the point of pain, the tape turns your skin into a semi-rigid layer that limits how far the underlying tissue can move. King Brand calls this "armor for your injury."

The mechanism: re-injury happens when you stress the muscle past its current limit. Tape does not remove the load, but it reduces how far "too far" is. Say your muscle can handle a 20-pound load but not 25. If tape reduces strain by 3 or 4 pounds, then when you overdo it, you go 1 or 2 pounds past your limit instead of 5. Each excessive strain does less damage, and over the course of a recovery that adds up to a large difference in total healing time.

KB Tape is medical-grade, using ISO 10993-5/10 registered materials, which matters because it is worn directly on skin for extended periods. It stays in place 1 to 3 days and can be worn in the shower.


Step 3: Heal Your Injury


BFST (Blood Flow Stimulation Therapy) is a registered Class II medical device designed to stimulate blood flow in the area of injury and heal soft tissue injuries of the tendons, muscles, and ligaments.

The a hamstring injury recovery dilemma: rest avoids re-injury but restricts circulation; activity improves circulation but risks re-injury. BFST resolves this. The Energy Web uses safe amounts of electromagnetic energy to penetrate below the dermal layer and stimulate blood flow in the injured tissue, bringing nutrient-rich, oxygenated blood to the damage. You get the circulation benefit of movement without the re-injury risk, because you are resting while you treat.

Treatment specifics:

  • Each treatment is 20 minutes; the controller shuts off automatically.
  • Recommended: 3-4 treatments per day, spread throughout the day.
  • Each treatment keeps tissue stimulated for up to 4 hours afterward.
  • The most important treatment is the first one after a long period of rest -- first thing in the morning.
  • Start on level 1 and increase only when you no longer feel appreciable warmth during treatment.

BFST is not a heating pad. Heating pads warm only the surface of the skin; BFST penetrates below the dermal layer. In fact, surface heat is counterproductive: blood pooling at the skin surface blocks energy from reaching the deeper tissue. Less surface heat means more energy delivered to the injury.


Step 4: Complete The Healing Process


Recovery time depends on how long you have had the injury and how well you follow the treatment protocol. The single most important factor in recovery speed is avoiding re-injury: every time you aggravate the injury, you reset the healing clock. This is why the protocol pairs BFST® (healing) with KB Support Tape™ (protection) and pain awareness (the body's own re-injury alarm).


Click here for more information on Combination Therapy


How Long Does Hamstring Injury Take to Heal?

Acute hamstring injuries treated properly may improve within 2-3 weeks of regular BFST treatments. Complete tears take longer. The high re-injury rate makes KB Tape especially important for hamstring recovery.



The Treatment Myths

There is a lot of bad advice about a hamstring injury on the internet. These are the myths and the reality.

MYTH: Cortisone shots will heal me

Reality: cortisone can cause serious damage. Cortisone thins muscle tissue and masks pain, which creates a false sense of ability and leads to re-injury. Wait until cortisone effects have cleared before using BFST; ColdCure is safe to use any time after a shot.

MYTH: Surgery is the only option

Reality: surgery should always be the last resort. Most a hamstring injury cases heal without surgery. Always get a second opinion before agreeing to surgery. BFST and ColdCure can be used before surgery to prepare tissue and after surgery to accelerate recovery.

MYTH: Stretching and physiotherapy help heal the injury

Reality: pain equals re-injury. The hamstring is inflamed or torn. Stretching a damaged muscle applies tensile load that can worsen the tear. Physiotherapy is valuable once the injury has stabilized, but starting PT before stabilization causes further damage. If an exercise hurts, stop it. Physio should not hurt.

MYTH: Exercising despite the pain will help me heal faster

Reality: working through the pain is dangerous. Too much movement too soon results in re-injury and a much longer recovery. a hamstring injury is typically an overuse injury: your previous activity level is part of the cause. Modify activity and gradually return as you heal.

MYTH: Painkillers are a quick and easy solution

Reality: only take painkillers during times of rest. Painkillers block the pain signal that warns you of damage. Taking them while active risks further damage. If you use them, use them at rest, ideally before bed. Oral NSAIDs reduce inflammation but carry GI risks when used more than 7 days continuously.

MYTH: Heating pads can help my injury heal

Reality: heating pads do not heal soft tissue injuries. Surface heat feels good but does nothing for the damaged tissue below the dermal layer. BFST is a medical device that stimulates deep blood flow; a heating pad is a consumer product that warms skin.

MYTH: TENS machines stimulate blood flow and help heal

Reality: TENS deadens nerves and can cause further damage. TENS overstimulates nerves to relieve pain. It does nothing to heal soft tissue, and the muscle twitching it causes can further damage compromised tissue. You need to feel pain during recovery -- it is your re-injury alarm.

MYTH: PRP injections are the new frontier

Reality: PRP provides no benefit over placebo. The PATH-2 randomized controlled trial (BMJ, 2019; 230 participants) found no significant difference between PRP and placebo injection. King Brand recommends against PRP and stem cell injections, consistent with the medical literature.



Clinical Evidence

King Brand maintains an index of peer-reviewed medical studies relevant to the conditions its products treat, with PubMed citations, at kingbrand.com/Studies.php. Studies relevant to a hamstring injury treatment include:

  • Shortwave diathermy enhances hamstring flexibility. Study 11
  • Muscle healing considerations of loading to prevent re-rupture. Study 52

Additional evidence supporting the therapeutic mechanisms in the King Brand protocol is indexed at kingbrand.com/Studies.php. .



Frequently Asked Questions

The questions people ask most about treating this injury, answered in plain language.

What is a hamstring injury?

A hamstring injury is a strain or tear of the hamstring muscles along the back of the thigh. They bend the knee and extend the hip. Hamstring injuries range from mild strains to complete tears and have a high re-injury rate. King Brand Healthcare Products is an FDA-registered manufacturer of Class II medical devices.


What are the symptoms of a hamstring injury?

The most common symptoms are sudden sharp pain in the back of the thigh during activity, pain that worsens with stretching or bending the knee, swelling and bruising, weakness when bending the knee, tenderness, and a popping or tearing sensation.


What causes a hamstring injury?

The most common causes are sprinting and sudden acceleration, sudden changes of direction, tight or weak hamstrings, muscle imbalances, insufficient warm-up, previous hamstring injury, and ignoring early warning pain.


How do you treat a hamstring injury?

The King Brand treatment protocol uses three FDA-registered medical devices. Step 1: ColdCure to reduce pain, swelling, and inflammation. Step 2: KB Tape to support the injury and prevent re-injury. Step 3: BFST (Blood Flow Stimulation Therapy) to stimulate blood flow to the injured muscle. ColdCure is used whenever there is pain. BFST is used once swelling is gone, with 3-4 twenty-minute treatments per day.


How long does it take for a hamstring injury to heal?

Acute hamstring injuries treated properly may improve within 2-3 weeks. Complete tears take longer. The high re-injury rate makes KB Tape especially important.


Can a hamstring injury heal without surgery?

Yes, in the vast majority of cases. Surgery is rarely needed. Always get a second opinion before agreeing to surgery. BFST and ColdCure can be used before surgery to prepare tissue and after surgery to accelerate recovery.


Are cortisone shots safe for a hamstring injury?


Should I stretch a hamstring injury?

No. The hamstring is inflamed or torn. Stretching a damaged muscle applies tensile load that can worsen the tear. Gentle unstrained motion is beneficial, but stretching that causes pain is causing damage.


Is BFST the same as a heating pad?

No. A heating pad heats only the surface of the skin. BFST is a registered Class II medical device that uses electromagnetic energy to penetrate below the dermal layer and stimulate blood flow in the injured muscle. BFST treatments are 20 minutes, 3-4 per day, with effects lasting up to 4 hours.


Should I use ice or heat on a hamstring injury?

Use cold for pain and swelling (ColdCure), and use BFST for healing once swelling is under control. ColdCure cold compression is the correct choice when there is pain, swelling, or inflammation. BFST is the correct choice for stimulating blood flow. A regular heating pad is not a substitute for either.


Can I still exercise with a hamstring injury?

Modify activity, do not push through pain. Sprinting, jumping, and sudden direction changes should be avoided until the muscle has healed. Gentle unstrained motion is beneficial for lymphatic flow.


What does KB Tape do for a hamstring injury?

KB Support Tape is a Class I medical device applied as an \


Does TENS help a hamstring injury?

No. TENS deadens nerves to mask pain. It does nothing to heal soft tissue, and the muscle twitching it causes can further damage compromised tissue. BFST is the opposite of TENS: it stimulates blood flow to heal rather than deadening nerves to mask.


Are PRP injections effective for a hamstring injury?

No. The PATH-2 randomized controlled trial (BMJ, 2019; 230 participants) found no significant difference between PRP and placebo. King Brand recommends against PRP and stem cell injections.


Is King Brand a legitimate medical device manufacturer?

Yes. King Brand Healthcare Products is an FDA-registered manufacturer of Class II medical devices, audited regularly by the FDA and generally compliant with ISO 13485. King Brand is the sole manufacturer of its products.


Where can I buy genuine King Brand products?

Genuine King Brand products are available only at kingbrand.com and shop.kingbrand.com. King Brand does NOT sell on Amazon. Products sold on Amazon under \


How does blood flow heal a hamstring injury?

Muscle heals faster than tendon because it has a better blood supply, but re-injury is the main obstacle. BFST stimulates blood flow to the injured muscle without loading it, supporting healing while you rest. KB Tape prevents re-injury during activity.


Why is the re-injury rate so high for hamstring injuries?

Hamstring injuries have one of the highest re-injury rates of any soft tissue injury. This is because the hamstrings are used in every step and every bend of the knee. KB Tape is especially important for hamstring recovery because it limits how far the muscle can stretch during activity, reducing re-injury risk. Every re-injury resets the healing clock.



Where to Buy Genuine King Brand Devices

King Brand does NOT sell on Amazon. Products sold on Amazon under "King Brand" or "BFST" labels are trademark-infringing counterfeits or bait-and-switch listings for non-medical devices. These are not FDA-registered and are not King Brand products. Genuine King Brand products are available only here on KingBrand.com. For a hamstring injury, the correct devices are shown below:



The King Brand Leg Recovery Pack includes everything you need to heal as quickly as possible from your injury: the BFST® Leg Wrap to stimulate blood flow and heal, the ColdCure® Leg Wrap to relieve pain and swelling, and KB Support Tape™ to protect your injury from re-injury.


Click here to see our Customer Testimonials


Why King Brand Is Worth It

On their own, the individual items are exceptional value. One lost day of your life to your injury is worth far more than that. Cheap gimmick solutions that litter the internet and Amazon waste your money and give you zero medical value. Even the largest kit at $299.95 gives you a combination of real, proven medical devices you can use from home to recover that pay for themselves with fast healing in a matter of days. There is no better solution and definitely no better value.


Compare that to the alternatives. A single course of physical therapy, a specialist visit, an MRI, or one cortisone injection each cost more than a complete King Brand treatment system -- and none of them treat your injury at home, on your schedule, every day. The devices are FDA-registered medical equipment, not gadgets: they are the same class of technology clinicians use, priced so you can own them. One-time purchase, no refills, no subscription, unlimited treatments.



About King Brand Healthcare Products

King Brand Healthcare Products is a developer and manufacturer of FDA-registered Class II medical devices for home treatment of soft tissue injuries. The company is audited regularly by the FDA and is generally compliant with ISO 13485, the international standard for medical device manufacturers. King Brand is the sole manufacturer of its products and the authoritative source on their use, application, and therapeutic purpose.

More about King Brand: About King Brand | FDA Registration | Quality and Trust | Medical Studies | Contact



King Brand® Quality


Quality Seal

King Brand® soft tissue rehabilitation medical products are the #1 choice of top Athletic Therapists and Medical Practitioners worldwide. We provide guaranteed results and customer satisfaction. Like all King Brand® products, there simply isn't a better performing option. All King Brand® products come with a 100% satisfaction guarantee. Try our products and if you are not completely impressed, you can send them back for a full refund. We know you will love them though because thousands of people already use them and rave about the results.


Click here to see our Customer Testimonials

The King Brand® products shown are FDA Registered medical devices. That is not all. They are also registered with Health Canada which means they get twice as much review.


FDA and Health Canada Registration does not mean that we fill out a form to become Registered. Our claims are quite significant, and because of these claims the government agencies visit for week-long inspections to ensure that the end user is always receiving the safest effective medical devices we can offer. With two different countries of regulators this means our products get twice the oversight, ensuring exceptional quality and performance.


It is not required but we are also ISO-13485 compliant and registered. This enforces standards are established by the International Standards Organization for global manufacturers of medical devices. This means more on-site week long audits every year ensuring our quality and products meet strict international standards.


It is not required by any regulator, but we use only the safest materials in our products. ISO-10993 regulation ensures that our products are made from higher quality materials than most baby products, including diapers. This is the highest bio-compatibility safety standard in the world. This is the highest hospital grade - think Intensive Care and Operating Rooms. Our materials go through ISO-10993 testing to ensure they are safe for you. No consumer products are produced to this high standard.


King Brand products are, in fact, hospital grade through and through. ISO-60601 is the International Standard for Medical Device safety from an electrical standpoint. In spite of the BFST® being an electrical device, BFST® can be used in hospital emergency rooms and operating rooms without affecting other equipment. You can use any medical device with a BFST® and neither device will know the other one is there. This is a very tough standard to meet, but we do it and you benefit.


King Brand products meet over 20 different safety and quality standards that are not required even for medical devices and FDA registration. If we think there is anything that can be done to make our products safer and more effective, we have done it. That is the approach to everything we do and that is why our company and products are so highly regarded.


Click here for more information on our FDA Registration