Posts Tagged ‘fasting’

Track your HRV to boost adaptive reserves

Posted 21 Jul 2014 — by Todd
Category Diet, Fitness, Health, Hormesis

Frustrated_man_at_a_desk_(cropped)Stressed out?

There’s a surprisingly simple but little-known technique for measuring your in-the-moment ability to handle physical, mental and emotional stress.  Some of us have a higher level of “adaptive reserves” than others.  And for all of us, these adaptive reserves increase or decrease throughout the day and over days or weeks.   You might have a rough, intuitive sense of when you are more resilient to stress, and when you are weak or more vulnerable. There is no shortage of advice on the Internet about “stress management”, fitness and diet.  In general, sleep, physical activity and a nutritious diet build adaptive reserves, while these reserves are easily depleted by chronic stressors like worry or overwork.

But how do you know what really works to improve your resilience and resistance to physical and psychic stressors?  How can you learn what diet, exercise, and activities actually work for YOU — not just what researchers, health professionals, bloggers or your friends claim should work?

What if I told you that there is a reasonably objective metric for your overall adaptive reserves and a simple, inexpensive, and noninvasive way to measure your adaptive reserves throughout the day.

The metric is called heart rate variability, or HRV. It can be measured in less than a minute, using an inexpensive chest strap or finger sensor, and any of several smart phone apps that can be downloaded for a few dollars. Based on a review of numerous studies and extensive personal experimentation, I’ve learned some surprising things about what tends to raise or lower HRV.  And I’ve found one few amazingly quick, effective, and to boost a low HRV and keep it up, with real impact on adaptive reserves.  (For the impatient, scroll to bottom of this post and read Recommendation #1).

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Calorie restriction and hormesis

Posted 23 May 2010 — by Todd
Category Diet

One of the first scientifically rigorous demonstrations of the benefits of hormesis was a 1934 study of calorie restriction (often abbreviated “CR”) in laboratory rats, conducted by Mary Crowell and Clive McCay at Cornell. They found that reducing the calories of rats by 30-50%, supplemented with adequate micro-nutrients, could almost double their lifespans. Later studies found continued lifetime extension with calorie restriction up to 65%. In addition, the rats remained energetic and youthful in appearance, with greatly reduced incidence, and delayed onset, of age-related diseases. This same phenomenon has been observed in a variety of other animals.

Studies on calorie restriction in primates or humans are as yet inconclusive. Controlled primate studies only started in the late 1980s and have yet to be completed, although the preliminary indications are very promising. And in humans it is more difficult to conduct controlled studies for both ethical and compliance reasons. An additional factor to consider is that animals raised post-weaning on calorie restricted diets typically have much smaller adult body sizes that animals not restricted in their eating.  Because of the social and physical implications of this consequence, advocates of calorie restricted diets for humans advise that they be started only upon reaching adulthood.

Whether or not a restricted calorie diet extends the human lifespan, the evidence is becoming overwhelming that a nutritionally complete diet with reduced calories has the potential to greatly improve our health, particularly as we age. But is it practical and possible for humans to happily adhere to such a diet?

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