Effect of Low-Level Laser Therapy and Strength Training Protocol on Hand Grip by Dynamometry

Area of Science:

• Sports Medicine
• Rehabilitation Science
• Biomedical Engineering

Background:

• Grip strength is crucial for daily activities and athletic performance.
• Low-level laser therapy (LLLT) is explored for its potential to enhance muscle function.
• Optimizing LLLT parameters for pre-exercise protocols requires further investigation.

Purpose of the Study:

• To evaluate the impact of 660 nm and 904 nm low-level laser therapy (LLLT) administered before grip strength training.
• To compare the efficacy of different LLLT wavelengths and a placebo LLLT in conjunction with resistance training.

Main Methods:

• 45 healthy volunteers participated, divided into control (placebo LLLT), 660 nm LLLT, and 904 nm LLLT groups.
• LLLT was applied to flexor muscles before a four-week grip strength training (Oxford protocol) and dynamometry assessment.
• Statistical analysis utilized the analysis of variance (ANOVA).

Main Results:

• The 904 nm LLLT group demonstrated a significant increase in grip strength compared to baseline after four weeks.
• A significant difference in grip strength was observed between the control group and the 904 nm LLLT group.
• No significant intragroup difference was noted for the 660 nm LLLT group compared to baseline.

Conclusions:

• Low-level laser therapy (LLLT) at 904 nm, applied prior to resistance exercise, effectively enhances grip strength.
• The 904 nm wavelength appears superior to 660 nm LLLT and isolated strength training for improving grip strength.
• Pre-exercise LLLT may be a valuable adjunct therapy for improving hand strength outcomes.