Which of the following is an example of light therapy?

• A. Whirlpool
• B. TENS unit
• C. Laser, light therapy
• D. Massage

Answer: (C)

Light therapy uses specific wavelengths of light to influence cellular processes, promoting healing and reducing pain and inflammation. The energy from the light is absorbed by cells, which can boost cellular metabolism, collagen production, and blood flow, while helping modulate inflammatory and pain signals. Laser, light therapy fits this approach because lasers (or light-emitting devices) deliver concentrated photons to targeted tissues, allowing precise treatment.

Whirlpool relies on warm water (hydrotherapy), a TENS unit uses electrical stimulation to affect nerves, and massage involves manual hands-on work—none of these use light energy to produce the therapeutic effects.