Scientific studies suggest that red light therapy can improve recovery after physical exertion. Use red light therapy after your workout for best effect, but any time during the day is fine too. Healing from injuries and pain above all needs NIR (near infrared light) as it is pain-relieving in itself, and it is probably better to split the treatment into a couple of shorter sessions especially in case of pain.
Dele:
How can I use red light therapy to improve my results in the gym?
Does red light therapy help with a muscle strain?