Increasing the challenge level means that the threshold is raised on what the emWave software considers to be medium and high coherence.
If the challenge level is rasied, the HRV wave has to be smoother to attain a high coherence score. It’s possible to use rhythmic breathing to get a high coherence score at the low and medium challenge levels, as breathing is the main physiological driver of the heart rhythm pattern. At the high and highest challenge levels, it’s essential to shift to a positive emotional state to get a lot of high coherence, as this produces a smoother breathing pattern than most people can produce with paced breathing.
HeartMath’s approach to HRV is to change how you feel, to change how you breathe, to change your heart rhythm pattern. Most systems focus solely on breathing, which is a good foundational step, but emotional self-regulation is our primary goal through the direct training of the emotions — “emotional muscle building” through the exercise of evoking a positive feeling on demand on a regular basis and monitoring performance and progress with the emWave technology.
Changing the Challenge Level
You will find the drop-down list near the upper-left corner of the window, next to the current user drop-down list:
- Low is the easiest challenge level and the default setting
- Medium is the second easiest challenging level
- High is the second most challenging level
- Highest is the most challenging level
NOTE – There is a 15% difference in the degree of difficulty between each of challenge levels 1, 2, 3. However, there is a 30% harder degree of difficulty in achieving and sustaining High Coherence in challenge level 4.
Setting a Default Challenge Level
You may also set a default challenge level for the current user:
Each user can have their own default challenge level and all new users start with their default challenge level set to Low.
Increasing the challenge level raises the threshold in the coherence algorithm for determining Low, Medium, and High coherence levels. The coherence scoring algorithm uses power spectrum analyses, a measure of frequency and frequency magnitude, of the heart rhythm to determine the amount of physiological coherence in the HRV waveform. By tracking the ratio of power in the coherence peak relative to the rest of the frequency spectrum a coherence ratio is calculated. The challenge level sets the level at which the algorithm scores the coherence ratio as low, medium or high. The higher the challenge level, the higher the coherence ratio score must be in order to accumulate coherence points. The more stable the frequency in both amplitude and frequency the HRV waveform becomes (visually this appears as a smooth regular sine wave like pattern in the HRV waveform) the more power is concentrated in the coherence frequency peak and thus the ratio of power in this peak relative to the rest of the spectrum.
Coherence in not strictly bound to the fixed boundaries of the LF (low frequency) region, most physiological processes vary over a range of frequencies. The coherence range spans from the top of the VLF (very low frequency) through the lower portion of the HF (high frequency) range of the HRV power spectrum (approximately 0.03-0.24 Hz). It is not necessary for the coherence frequency to be at 0.1 Hz to be coherent, although 0.1 Hz is the center of the range around which the coherence or resonant frequency typically occurs when looking at large samples of the population. Each person tends to naturally find their own resonate frequency which can vary some from day to day or with different states.