Thermotherapy can be an effective treatment in facilitating the healing process if it is used properly.

However, the application of heat too early can exacerbate tissue damage in an acute injury and actually prolong the healing process.

Understanding how and when to use heat is important in the care and treatment of injuries.

When should heat be used to facilitate healing in an injury?

It is important to understand a little bit about how the body heals to understand how and when heat should be used to treat injuries. The most frequent question I receive is “Should I be using heat or ice?”.

This got me thinking. Surely there is an easier way to remember when to use heat and when to use ice. What you should know is that there are different reasons for using the two modalities and there are phases in the healing process that have a purpose. So if we understand and remember what they are it will make for a quicker recovery.

The first phase is known as the inflammatory phase. The goal during this phase is to protect the injured area from further injury, whilst the body starts the healing process. When an injury initially occurs, there is damage to the soft tissue structures (ligament, muscle, and tendon) but also damage to the blood vessels immediately in the area.

The damage to the blood vessels causes fluids to build up in the injured area causing the swelling that is typically seen in a new injury. To help reduce the flow of fluid into the area and thereby reduce swelling, cryotherapy (cold applications) is the best modality to use right after an injury. Cold modalities can help slow down and decrease the circulation to the area thereby reducing swelling.

Heat applied during this phase is contraindicated because heat increases blood flow into the injured area significantly increasing the amount of swelling. Increased swelling prolongs the rehabilitation process because it takes time to reverse the process and remove the extracellular fluid.

This first phase of the healing process can last for several days depending on the amount of tissue damage. For most injuries, two days is the most common time frame for phase one and is when ice should ONLY be applied to injuries.

The second phase of the healing process is known as the proliferation phase and is characterized by the laying down of new tissue and the formation of scar tissue. Again, depending on the amount of damage to the injured area, this phase can begin on post-injury day three and last for several weeks.

IT IS DURING THIS SECOND PHASE OF HEALING THAT HEAT CAN BE APPLIED TO THE INJURIED AREA TO FACILITATE THE HEALING PROCESS. The person can determine if he/she has entered phase two of healing when the initial swelling and pain of the injury starts to decrease.

Heat therapies can also be used during the third and final phase of the healing process known as the remodelling phase. During this phase the new tissue laid down during phase two matures. This phase can last up to one full year depending on the type of tissue that was injured.

When heat is applied during the second phase of healing, a number of physiological effects occur including:

  • Increase in circulation to help remove debris and waste products
  • Increase in cellular metabolism
  • Increase in capillary permeability
  • Provide an analgesic effect- this is why people feel more comfortable with heat.
  • Reduce muscle spasms
  • Increase in oxygen and nutrients into the area to promote healing
  • Increase in extensibility of muscle and connective tissue to help facilitate stretch and elongate tissue

Heat has been found to be effective at reducing the pain associated with muscle spasms by providing an analgesic effect and relaxation effect for tight muscles. For small muscle spasms, moist or dry heat packs can be effective. Larger areas can be treated by full-body immersion in a spa.

Heat therapy is also effective in increasing the range of motion of joints after injury. Once the swelling from the original injury begins to subside, the injured area can be heated using a warm spa or hot pack for 10 -15 minutes.

Because tissue becomes more extensible after it has been warmed up, range of motion exercises can be performed after heating to improve joint motions. The goal is to gradually increase the range of motion of the joint and restore it to pre-injury levels. However, care must be taken to not push a joint through pain as this can actually reinjure the tissue.

If you are prone to injury or have a current injury and you are unsure how to manage the injury please contact Elite Myotherapy today to arrange an appointment.

By Ebony Hamilton – Elite Myotherapist