Heat (thermotherapy): Put in the microwave, flat and without its cover, for 30 seconds at 600W. Then wait 30 seconds before use. Take it out of the microwave, massage so that the heat is homogeneous and place it in its cover before use. It can also be used with hot water. Place the bag, without its cover, in a pan of hot or boiling water (about 55°C, no more than 60°C) off the heat for 6 to 10 minutes. Remove the bag from the water, dry it with a handkerchief and massage it so that the heat is homogeneous. Place in its cover before use.
Cold (cryotherapy): Place the Bodypack thermal bag, without its cover, in the freezer for at least 1 hour. Remove from the freezer and dry with a tissue. Put it on its cover before use.