EmWave, Heart Rate Variability (HRV), Vagal Tone. These are all terms that bio-hackers have heard and know about to some degree. One of the leaders in this space is the HeartMath institute and Rollin McCraty from HeartMath was one of the presenters at the third day of the Bulletproof Conference 2013. We want to share some of the lessons we learnt from his presentation.
The HeartMath Institute uses a product that they produce (called the "EmWave") to run resilience programs for various organisations including the US Navy - we can all imagine some of the high stress situations Navy personnel can be in and how keeping your head (no pun intended!) can increase the likelihood of a positive outcome. The basis of the resilience training is learning a set of conscious, trained techniques to achieve, maintain, and return to a state of "Coherence"(Synchronisation between heart, brain and sympathetic/para-sympathetic nervous system). Being able to take conscious control of your state of mind is one of the foundations of sustained performance and optimal health. Achieving coherence means having the sympathetic and parasympathetic nervous system in sync (according to Rollin it follows that a lack of coherence is the physiological driver of why we do stupid things when we are pissed off).
So why does this work? Well, the heart sends much more information to the brain than the other way around. There is is an entire field of medicine called neuro-cardiology dedicated to this. The heart signals especially affect the brain centers involved in strategic thinking, reaction times, social awareness, decision making, creativity and self-regulation. For all you Neuroleadership folk you'll know this as being the relationship between your limbic system and pre-frontal cortex (PFC). Whenever your limbic system activates it puts a load on your PFC and your executive function diminishes leading to another cascade of increased limbic dominance.
Biohacking conference slide: When we are in a state of coherence, we are in control.
A key point from Rollin's presentation was that coherence begets resilience.You can train to become more resilient, which means that you can improve your ability to prepare for, recover from and adapt in the face of stress. Resilience is about understanding your body's depletion and renewal cycles and being able to turn on that switch (to make the light on the emwave go green) at will. If you can go to that "happy place" (coherence) then you can switch off that stressor before you are depleted and "done for the day".
To be in a coherent state your heart rate needs to actively responding to your breath rate. The state of coherence is based around the fact that it is more energy efficient for your body to beat your heart faster when you've got a lung full of fresh air rather than empty lungs "full" of stale air. You want to grab as much of the oxygen out of your lungs as you can. If your heart rate is instead responding to how stressed you are (and how un-mindful you are being) then your sympathetic and para-sympathetic nervous systems are out of balance. This is the uneven chart from the above slide.
There are over 80 published studies[1] that demonstrate the benefits of HRV training.
The Framework for How to be Resilient Using the EmWave or Inner Balance Trainer
Heart Rate Variability training is available through 2 Heartmath devices:
| Stand alone emWave2 | Inner Balance Trainer for Apple iOS | Bluetooth Inner Balance Trainer |
 Works with a clip on ear sensor. Training session data can be uploaded to a computer to track progress. |
|
Works with all Bluetooth compatible smartphones and tablets on Apple or Android that can run the Inner Balance app. |
In this edition of Biohacking Weekly:
1. Caffeine’s surprising rhythm fix
2. The medicine you can look at
3. Why awareness won’t heal your gut
4. Does melatonin really harm your heart?
5. Aging, NAD+ and longevity pathways
This guide breaks down the most popular science-backed biohacking supplements of 2025, focusing on compounds that support cellular energy, metabolic health, and longevity. Each selection is grounded in clinical research and growing real-world adoption.
In this edition of Biohacking Weekly:
1. The nutrigenomics effect
2. Dr. Peter Attia on your body’s “engine size”
3. The microbiome shortcut to ending constipation
4. How bright nights turn into heart trouble
5. Gluten sensitivity isn't about gluten
