If you’re a Cardio Hound, you may find yourself in the gym going “all out” 3-5 days a week, bouncing around between various forms of high intensity training — maybe even doing back to back high intensity classes. And if the gym isn’t your forte, maybe you log several miles a day on your daily run but just can’t seem to get down to your target weight. If so, you may be doing your body more harm than good.
While most of us aren’t moving enough and are clearly suffering the consequences, some of you may be frustrated that the hours and hours you are putting in just don’t seem to be paying off. We’ve all been told forever – burn more calories/lose more weight. So what gives?
The human body was not designed to be moving at a high intensity for a sustained period of time repeatedly. In fact, there are specific physiological deterrents to this type of movement, which we’ve all been told over and over again to “push through.” During high intensity bouts of movement, your body releases the stress hormone Cortisol. From an evolutionary perspective, Cortisol is a survival mechanism designed to aid us in the face of danger. But sustained high levels of Cortisol in the blood stream are toxic and will flaunt your weight loss efforts. While you bust your butt, Cortisol encourages the body to store fat and retain water. Both of which are critical to surviving a stressful encounter. Not only that, but sustained high levels of Cortisol will make you susceptible to infection, injury, loss of bone density, and depletion of lean muscle tissue.
Here is a great perspective by Primal guru Mark Sisson:
“Our hunter-gatherer ancestors didn’t regularly ramp their heart rates up for over an hour a day like so many of us do now. Even when the concept of organized hunting came along, it would appear that our hunter-gatherer ancestors relied more on superior tracking ability (using our highly evolved and exceptionally large brains) and walking (using our superior fat-burning systems), rather than on actually “chasing down” their prey. In fact, squandering valuable energy reserves (and increasing carbohydrate [glucose] metabolism by a factor of ten) by running hard for long periods of time was so counterproductive it would have likely hastened your demise (imagine chasing some game animal for a few hours and – oops – not succeeding in killing it. You’ve spent an incredible amount of energy, yet now you have no food to replace that energy. You have suddenly become some other animals prey because you are physically exhausted).”
Cardio Hounds will pay in other ways as well including:
- Decreased fat metabolism efficiency
- Increased systemic inflammation
- Increased oxidative damage (free radical production)
And lets not forget, with all of that caloric expenditure, you gotta eat! ALOT! The body is an economic machine — constantly in a state of caloric conservation. When calories are expended, the body looks for ways to replace those lost calories — either through rest or diet. And since sugar is the fuel source being burned at this high heart rate, carbs/sugar is what you crave. Bring on the pasta/oatmeal/bread/etc. — all of which spike insulin and store fat.
So what is the perfect amount of exercise and what does it entail? To answer this question, all we have to do is hop in our Evolutionary Time Machine and think back to how our ancestors moved and how often they did it.
The typical week consisted of a high amount of low intensity movement. Gathering, forging, tracking prey. Then came occasional bouts of high intensity — fight or flight moments that required us to kill or be killed. This may have happened once or twice a week and only lasted a few minutes. To round it out, our ancestors built things, moved things and played!
So how can you translate this to your neolithic lifestyle?
- Move Frequently at a Slow Pace: 55-75% max heart rate, 2-5 hours a week. Walking, hiking, cycling, easy cardio. Strengthens the cardiovascular and immune systems, promotes efficient fat metabolism and gives you a strong base to handle more intense workouts.
- Lift Heavy Things: Brief intense sessions of full body, functional movement. 1-3 times per week for 7-60 minutes. Stimulates lean muscle development, improves organ reserve, accelerates fat loss, and increases energy.
- Sprint Once in a While: ”All out” efforts, <10 minutes total duration once every 7-10 days. Stimulates the production of HGH and testosterone, which help improve overall fitness and delay the aging process – without the burnout risk of excessive prolonged workouts.
Avoid:
- Chronic Cardio: Frequent medium-to-high intensity sustained workouts
- Chronic Strength Training: Frequent and/or prolonged sub-maximal lifting sessions ending in exhaustion
- Regimented Schedules (instead, allow for spontaneous, intuitive variation in type, difficulty and frequency of workouts)

