Meet Mark

Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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Tag: dear mark

Dear Mark: Cycling Harder Than Running, High-Fat Football Training, and Orange Theory

For today’s edition of Dear Mark, I’m answering three questions about training. First, why might cycling feel harder than running at the same heart rate, and what should be done about it? Second, is it safe or smart for a footballer to try to become a fat-burning beast when he’s currently in-season? Are there lessons can we draw from athletes who have given it a shot?

And finally, what do I think about the relatively new Orange Theory gyms that have arrived on the fitness scene? Are they good, bad, or both?

Let’s go:

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Dear Mark: Higher BMI and Mortality Risk, Calories When Meal-Skipping, HIIT After Fasting

For today’s edition of Dear Mark, I’m answering a couple questions from you guys. First, there’s a new paper out claiming that the ideal BMI for overall mortality is an overweight one—27, to be exact. Is this really the case? Should we all pack on a few extra pounds to see us through into old age? Next, should you try to make up for all the “lost” calories when you eat in a compressed eating window? If you skip breakfast, should you try to eat more at lunch? And finally, how does one incorporate high intensity interval training on a low-carb diet that includes fasting?

Let’s go:

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Dear Mark: Lead in Bone Broth, Cooked and Cooled Potatoes, and Stress Strategies

For today’s edition of Dear Mark, I’m answering three questions. First one concerns the lead content in bone broth. A 2013 study reported elevated levels of lead in chicken bone broth. And not the canned or boxed stuff, but the real thing: broth made from actual chicken bits. Should you worry? Second, do cooked and cooled potatoes really make the carbs less problematic for people who typically try to avoid them? How and why should people who otherwise avoid potatoes consider eating cooked and cooled ones? And finally, do I have any good, simple strategies for dealing with stress? Why yes, yes I do.

Let’s go:

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Dear Mark: Is Caloric Density the Answer?, Fat Starving the Brain, and High-Intensity Primal Endurance Training

For today’s edition of Dear Mark, I’m answering three questions from readers. First, should the primary focus in constructing a healthy diet be caloric density? Is the key to weight loss and optimal health the consumption of bulky, low-calorie foods? Next, a new study seems to show that fat “starves the brain.” Is this true? If not, what’s really going on? And finally, are following Primal Endurance principles antithetical to high intensity performance?

Let’s find out.

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Dear Mark: Saturated Fat Jet Lag, Collagenous Amino Acids, and Different Cutting Diets

For today’s edition of Dear Mark, I’m answering three questions. The first concerns a recent study seeming to show that saturated fat disrupts our circadian rhythms, especially saturated fat at the wrong time of day. Should we—yet again—trade butter for soybean oil? Second, how necessary are the amino acids found in collagen? Aren’t they found all over the place, not just in collagen? And finally, I answer a couple questions about cutting diets (those traditionally low-fat, low-carb, high-protein diets) and if they can be adapted to a primal way of eating.

Let’s go:

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Dear Mark: Just Outside of Goal Weight, Skipping Breakfast and Coffee, and Quark

For today’s edition of Dear Mark, I’m answering four questions. First up, I discuss what to do—and really, what not to do—as you approach your goal weight but keep coming up short. Second, why do breakfast skippers also tend to be the biggest coffee drinkers around? Is it just correlation or is there a causative explanation lurking within? And finally, what’s the deal with the cultured dairy product known as quark? Is it a worthwhile addition? Is it safe, given its decidedly neolithic origins?

Let’s go:

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Dear Mark: Vegetarianism Causes Cancer?; Glucosamine Useless?; Decision Fatigue Debunked?

For today’s edition of Dear Mark, I’m answer three questions. First, does long-term vegetarianism cause cancer or alter our genetic code? Some media coverage of the latest vegetarianism study seemed to suggest as much. Next, is glucosamine just totally useless if you’re not going to fork out a ton of money for pharmaceutical grade stuff? Maybe not, but let’s find out. And finally, I’ve written about decision fatigue a couple times before. What’s my take on the new research seeming to debunk one of the central concepts supporting it—ego depletion/finite willpower?

Let’s go:

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Dear Mark: Do I Need to Eat More, Testosterone Levels, HRV and Carbs

For today’s edition of Dear Mark, I’m answering three reader questions. First, if things are going well on a relatively low-calorie intake, should you just keep on keepin’ on or should you increase food intake to “get ahead” of your needs? Next, what’s the deal with a study showing a high-carb diet is better for testosterone levels than a high-protein one? What does this mean for your Primal way of eating? And finally, can an improvement in heart rate variability after a carb refeed indicate a greater need for carbs?

Let’s go:

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Dear Mark: Staying Aerobic, Glycogen Depletion, and Sleep-Low for Strength Training?

For today’s edition of Dear Mark, I’m answering three reader questions. First, do anaerobic workouts—sprints, lifting, etc.—interfere with your ability to become a fat-burning, aerobic beast, or can you integrate them? Next, in last week’s post I talked a lot about glycogen depletion in the context of the “sleep-low” carb partitioning. How can we actually achieve this without doing the intense intervals the elite triathletes were doing in the study? And finally, does carb-fasting after strength training also work?

Let’s go:

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Dear Mark: Bodyweight with Weights; Glycemic Index Versus Load

For today’s edition of Dear Mark, I’m answering a pair of questions from readers. First comes from Gaspare, who heard me talking on Joe Rogan’s podcast in January and wonders whether bodyweight training and weight training can complement each other. It turns out they can. Then, I discuss glycemic index, glycemic load, how foods can have low glycemic loads but still be bad for weight gain, and how focusing on glycemic index and glycemic load might be misleading, if not an outright mistake.

Let’s go:

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