Light Therapy (photobiomodulation) is a convenient, scientifically-backed way to stimulate the strength and recovery of cells in the human body⁵. Some of the key benefits of photobiomodulation therapy include increased performance among all athletes, as well as faster recovery from over-exhaustion. However, many athletes wonder if there are any risks when it comes to applying Light Therapy to their training program.

The best way to measure the success of certain training aid is to pay attention to the evidence behind it, especially for any negative side effects that may be associated with it. With a 50-year history of no reported or demonstrated negative side effects⁵, Light Therapy is a scientifically proven method and is safe to use.

Multiple studies have been carried out by researchers to look at the effects of Light Therapy on the human body, especially those focusing on benefits for recreational and professional athletes.

Light Therapy Can Boost Aerobic Training Performance Among Athletes

In a research effort that aimed at checking whether Light Therapy can improve performance in cyclists, an international team of scientists from Canada, Portugal, and Brazil examined effects among 20 competitive male cyclists who regularly engage in cycling for more than 4 days per week, capable of riding around 162 miles⁹. As noted by the study authors, the cyclists aged 29, "participated in a crossover, randomized, double-blind, and placebo-controlled trial." Each study participant came into the lab 2 times over a 5-day period to receive either a Light Therapy treatment or placebo on their thigh (quadriceps) muscle. All cyclists were blinded, so couldn't tell if they were really receiving the treatment or not.

After the Light Therapy treatment, the researchers measured maximal power output and endurance; this is known as the time-to-exhaustion tests (TTE). As part of the effort, each cyclist was also asked to maintain their maximum power output for as long as possible.
The researchers observed a reduction in Oxygen deficit as well as increased time-to-exhaustion (TTE) among those cyclists who underwent a Light Therapy treatment. A reduction in "Oxygen Deficit" means that an athlete's body can start using oxygen more quickly when starting aerobic exercise, saving precious energy¹³. Light Therapy can make the mitochondrial stronger, which means the body starts to consume oxygen more rapidly. This study proved that athletes can go longer during aerobic exercise after Light Therapy treatment.

What About "Less Aerobic" Activities such as Weight Lifting?

One of the best clinical methods to quantify muscle injury is by using indicators such as the MVC index¹⁶. MVC stands for maximal voluntary contraction¹¹ or the maximal amount of force or torque that a person can develop in a muscle.
In a double-blind and randomized study that looked at how Light Therapy can improve strength¹⁰, 10 male professional volleyball players performed biceps curls at 75% maximum strength (MVC) until exhaustion. The study participants received either Light Therapy treatment or placebo (PBM machine turned off) to their biceps muscle before exercise. Neither participants nor the researchers knew if someone received a Light Therapy treatment or not.

The Light Therapy treatment group experienced:

• An increase in endurance (13% higher number of repetitions and 12% longer amount of time doing the repetitions) compared to participants who were subjected to placebo¹⁰
• Delay in muscle fatigue by reducing the muscle damage and inflammation caused by exercise¹⁰.

Additionally, the Light Therapy group was able to use aerobic energy generation, saving them precious energy, as researchers of the study were able to observe a decreased blood lactate levels among PBM receivers. That is a byproduct of non-aerobic energy generation, which becomes present when the oxygen-based methods in the body can't keep up⁸.
The key highlight in recovery was that the Light Therapy group prevented muscle damage and inflammation (measured by the biomarkers C reactive protein and Creatine Kinase)³. Light Therapy increased their performance and the amount of exercise-induced damage, resulting in better training.

Can Light Therapy Increase Performance in Non-Trained People?

The short answer is yes!

In another randomized, double-blind study, 22 untrained men (22-25 yrs old) had either a Light Therapy treatment or placebo applied to their quadriceps, hamstring, and calf muscles⁶. Following the treatment, each participant was asked to run at a steadily increasing pace until reaching exhaustion.
Researchers were able to observe several differences between those who received Light Therapy and those who didn't.

The Light Therapy treatment group experienced:

• Improved endurance performance since they scored better on the time-to-exhaustion test
• Measured increase of use of oxygen in the body (VO2 max), that is a widely used indicator for cardiorespiratory fitness (and is particularly applicable for such exercises where the intensity increases incrementally¹⁵)
• Less muscle damage, which was tracked by various biomarkers for muscle damage such as lactate dehydrogenase⁷ and creatine kinase⁴
• Preserved strength of their muscles by having less oxidative stress within their body as measured by a decrease in fat damage¹⁴ (fat/lipid damage being an important factor for oxidative stress, that is a cellular process which leads to an impairment of muscle contraction¹²).

In a nutshell, untrained runners who received Light Therapy treatment within this study experienced better performance, reduced oxidative stress, and protective effects against exercise-induced muscle damage.

Can Light Therapy Help Prevent Muscle Fatigue and Increase Performance?

Another weightlifting study found that Light Therapy can decrease the amount of fatigue during knee extension exercises. For this study¹⁷, healthy and active men either received a Light Therapy treatment or a placebo. The targeted muscles were quadriceps. All study participants were then asked to perform 30 maximal knee-extension exercises at the same pace. All 17 men also measured no differences in their MVCs (their maximum strength).
The study showed that after the fatiguing exercise, the Light Therapy group experienced a 5% higher MVC than the placebo group¹, which means that Light Therapy can preserve your strength for longer.

Recovery with Light Therapy After Exercise

"A fast muscle recovery is important to athletes, especially during competition, since athletes commonly return to training approximately 48 h following a competition," says Dr. Borges, one of the co-authors of a study that asked 17 men to perform 30 biceps curls in a row using their non-dominant arm². This study focused on the recovery effects among those men who received Light Therapy and those who didn't.

In the four days that followed, the researchers tested two groups four times to find out that the largest recovery effect was demonstrated after 24 hours among the participants who had received a Light Therapy treatment after exercise². Muscle soreness, strength loss, and range of motion of the participants who received Light Therapy were decreased by the mechanisms of Light Therapy.

All these rigorous and evidence-based studies demonstrate that Light Therapy can increase performance, decrease exercise-induced muscle damage, as well as decrease recovery time.

If you are an athlete or an active person and want to learn more about Light Therapy treatment, connect with us on Facebook or Twitter and get the latest updates and news from the Light Therapy world. To experience the benefits yourself, book your FREE session here.

The Light Lounge Resource Center sources its data and research from peer-reviewed journals and unbiased world-class research institutions. Follow our blog to learn more and discover what the best research in the world has to say on Light Therapy (photobiomodulation treatment).