Therapeutic Pulsing Frequencies
Understanding continuous wave vs. pulsed laser therapy: when pulsing matters, which frequencies are most commonly used, and what the research actually shows.
The core technology of laser therapy is based on delivering a defined dosage of light energy to damaged tissue. Historically, this was done using continuous wave (CW) lasers, which produce the shortest treatment times. But over the years, more manufacturers have emphasized pulsing as key to success.
This guide analyzes the market to identify trends and consensus on pulsing frequencies, reviews the most popular options, and provides practical recommendations.
Why Pulsing Was Developed
Pulsing was originally developed for practical reasons: it allows the laser to stay cooler (because the laser is off part of the time) and treatment is safer due to reduced eye damage potential. But research has revealed additional advantages.
Thermal Management
Pulsing allows higher peak power without overheating. The off-time lets both the diode and tissue cool, enabling more energy delivery without burns.
Safety
Super-pulsed lasers with very low duty cycles are significantly safer because the average power is much lower than peak power, reducing eye damage risk.
Biological Stimulation
Certain pulsing frequencies appear to stimulate specific systems in the body. Research shows pulsed light may be superior to CW for many applications.
Preventing Adaptation
The human body is adaptive. Push on one spot long enough and you stop feeling it, like wearing clothes. Pulsing makes it harder for the body to adapt, potentially improving long-term treatment outcomes.
Continuous Wave vs. Pulsing vs. Super-Pulsing
Continuous Wave (CW)
The laser is on 100% of the time. Delivers maximum dosage in minimum time. Some manufacturers like Apollo build CW-only lasers, arguing we don't really know the optimal pulsing frequency, so why complicate things?
Best for: Fast treatments, acute conditions requiring few sessions, practitioners who want simple protocols.
Pulsed Wave (PW)
The laser turns on and off at a defined frequency. Duty cycle (ratio of on-time to total time) determines how much this extends treatment time. High duty-cycle pulsing (70-90%) delivers most of CW's dosage while still providing pulsing benefits.
Best for: Long-term treatment plans, conditions requiring biological stimulation, preventing adaptation.
Super-Pulsed
A high-power laser pulsed at very low duty cycle. Provides high peak power but is extremely safe because it generates minimal heat. Used by TerraQuant/MR4, TheraLase, Lumix, and K-Laser.
Best for: Home use, situations requiring maximum safety, practitioners emphasizing pulsing over dosage.
The Pulsing Trade-Off
Any time the laser is pulsing, it's off some of the time, decreasing dosage and extending treatment time. Some manufacturers use very low duty-cycles to allow cheaper diodes with little cooling. Higher-end systems offer high duty-cycle pulsing that maintains most of the dosage while providing pulsing benefits.
Interestingly, one study by Dr. Morries showed that high duty-cycle pulsing counter-intuitively increased the amount of energy reaching sensors buried deep in test samples, suggesting pulsing may actually improve penetration.
What the Research Shows
Al-Watban Wound Study
Compared 100, 200, 300, 400, and 500Hz using a 635nm laser. Found 100Hz was most effective for wound applications. (Note: Study was supported by Erchonia.)
Brain ATP Study
In a study on rabbit brains, CW radiation raised cortical ATP levels by 41%, while pulsed administration raised levels by over 150%. Pulsing was far superior for neurological applications.
Hamblin's Comprehensive Review
Dr. Hamblin, one of the most respected phototherapy experts, concluded that pulsed light appears superior to CW for most applications, particularly wound support and post-stroke management. However, CW may be better for nerve regeneration.
His theory: cells may need periods of rest, without which they can no longer be stimulated further. He recommends 10Hz for brain-related therapies, with an effective range of 10-40Hz.
"CW light is the gold standard and has been used for all LLLT applications. However, this review of the literature indicates that overall pulsed light may be superior to CW light with everything else being equal."— Effect of Pulsing in Low-Level Light Therapy (peer-reviewed study)
Most Commonly Used Frequencies
Based on manufacturer recommendations, research studies, and clinical practice, these are the most commonly recommended pulsing frequencies:
Thor recommends this for most applications requiring cellular stimulation.
Brain-related therapies. Dr. Hamblin's recommended frequency for neurological applications.
One of the most popular frequencies in Avant's 80+ presets. General-purpose stimulation.
Used in most Multiradiance/TerraQuant protocols for cellular stimulation.
Wound applications. Research showed this was optimal compared to 200-500Hz.
Recommended for most conditions on higher-end Multiradiance systems.
European standard. Universal frequency used for almost any condition, but especially surface tissue.
Pain reduction. Higher frequencies are generally considered inhibitory rather than stimulatory.
Nogier Frequencies (European Standard)
Nogier frequencies are among the most commonly recommended pulsing frequencies, especially among practitioners trained in European methods. Each frequency is thought to resonate with tissue originating from different embryonic layers.
Stimulatory vs. Inhibitory
A key concept in pulsing is the difference between stimulatory and inhibitory effects:
Stimulatory
Generally lower frequenciesPromotes cellular changes, ATP production, and tissue regeneration. Most commonly recommended for conditions requiring the body to rebuild or repair.
Common frequencies: 2.5Hz, 10Hz, 50Hz, under 100Hz generally
Inhibitory
Generally higher frequenciesReduces pain, calms inflammation, and decreases cellular activity. Better for acute pain management where you want to quiet the nervous system.
Common frequencies: 1000Hz+, variable sweeping, continuous wave
Thor recommends 2.5Hz for stimulation and continuous wave for inhibition. Multiradiance considers 50Hz stimulatory and 1000Hz+ inhibitory. The exact cutoffs vary by manufacturer.
Practical Recommendations
If you're buying a new laser
Get a system that does both pulsing and continuous wave if it's within your budget. This gives you maximum flexibility. Use pulsing for most applications.
If you don't have training in specific frequencies
Don't spend too much time trying to find the perfect pulsing frequency. Use a general frequency in the 2.5Hz to 292Hz range and you'll be in the therapeutic window for most applications.
If you want maximum flexibility
Look for a high duty-cycle programmable pulsing laser. This lets you deliver both pulsing benefits and adequate dosage with total control over frequencies.
If you just want fast, simple results
A CW-only laser is fine for acute conditions that will resolve in a few treatments. Pulsing is more important for long-term treatment plans.
Key Takeaways
Pulsing appears superior to CW for most applications except nerve regeneration, where CW may be better.
No consensus exists on the single best pulsing frequency. Common recommendations include 2.5Hz, 10Hz, 50Hz, 100Hz, 250Hz, and 292Hz (Nogier A).
Lower frequencies (under 100Hz) tend to be stimulatory; higher frequencies (1000Hz+) tend to be inhibitory (pain control).
High duty-cycle pulsing gives you pulsing benefits without dramatically extending treatment time.
Buy both CW and pulsing if budget allows. This provides maximum flexibility for different conditions and treatment goals.
Need help choosing a laser with the right pulsing options?
We can help you find a system that matches your treatment philosophy—whether you want full programmability or simple, effective protocols.