Cholesterol and Fat

I had a conversation with a friend last night about milk and how I like organic whole milk in comparison to skim milk. She was stunned that as a trainer I advocate the higher fat version of milk. However, I stick to my guns because the whole milk is more natural, has less added sugar and less refinement. Besides the milk fat and protein (casein and whey) is good for you. The discussion took a turn when she said what about clogging your arteries? Well let's look at the role of fat intake, cholesterol, and "clogging" our arteries. Here goes....

Let's begin with cholesterol. There is an overall fear of it in America and westernized countries, that we need to control our cholesterol levels, and the dogma seems to be that lower is better. I have to disagree, but let's save that for later. First, what is cholesterol? Cholesterol is a solid alcohol (not that kind) chemical that is soapy to the touch. Only a small percentage (around 7%) is circulated in the blood, the other 90-something percent is stored in every cell of the body as one of the constituents of the cells membranes (the things that regulate the flux of nutrients and hormones in and out of the cell, basically the liner of the cell). Also, cholesterol is used to make hormones, literally the building blocks. These hormones are involved in blood pressure, sex hormones (testosterone and estradiol), etc. If there is a lack of cholesterol you could test pathologically low for sex steroids (not good if you like a normal sex life, sex characteristics, and normal moods). Furthermore, cholesterol is involved in brain and peripheral nervous system development among other things. At any rate, the bottom line is we need cholesterol to do a bunch of things, and lowering it to extreme levels would not be advantageous to chasing health. What about cholesterol and it's respect to food intake? Well it's a lot smaller than we think. Read on....

Only a fraction of the cholesterol in our body comes from dietary intake (~15-20%), and the rest is produced by the body (mainly the liver, but also the intestines and skin). What's more, if you decrease your cholesterol and cholesterol stimulating foodstuffs intake, your body will just rev up the cholesterol production to meet its needs, and if you eat more cholesterol/cholesterol producing foodstuffs your body will ramp down the production. In people with very high cholesterol levels (over 220-250ng/dL or similar) simply eating less cholesterol will not warrant a significant change. What we need to address is the internal mechanism of cholesterol production. The actual main issue with cholesterol levels, is that too high levels in the blood can cause some issues (we'll get to that later), and the body can't regulate the blood levels. Cells constantly need cholesterol for repair and regeneration, but don't always just take it from the blood, sometimes they just make their own. Also, cells don't know how much cholesterol is floating around outside that specific cell, they just know what they have. So if they need to get some cholesterol for various processes, they'll just make it, completely oblivous to any aberration in blood cholesterol levels.

So we have this cholesterol floating around, and it's usually in one of 3 forms. VLDL, LDL, and HDL. At this point, most people know that LDL is the bad cholesterol, and they carry around mostly all cholesterol molecules to body tissues. It can do one of 3 things, be removed from circulation via the liver, absorbed by tissues needing cholesterol, or be deposited in the arteries. So how do we lower LDL blood levels so none is laid down in the arteries? Well to remove as much LDL as possible we need to get them in contact with as many LDL receptors (in the liver and other tissues) as possible. Cells that need more cholesterol send receptors (LDL receptors) to the cell surface to aquire the LDLs. Then they pull them inside and remove them from the blood. So, simply enough, we just need to increase the LDL receptors in tissues to get rid of LDL in the blood. However there is another side of the equation, if we can't significantly increase LDL receptors in each cell, we need to limit the production of cholesterol inside the cell, so that at least we give ourselves a shot at scavenging LDL particles with our few LDL receptors. At the same time we start sending our LDL receptors to the cell surface, we crank up the machinery to produce cholesterol within the cell. How does this happen?

When we have our LDL receptors out trying to get LDL from the blood, we are simultaneously acruing the raw materials to make cholesterol within the cell to meet the demand. There is one enzyme that is crucial to this in-cell synthesis, and it's HMG-CoA. Most cholesterol lowering drugs (statins) reduce this enzymes activity, and thus lower cholesterol production. However, we can do this naturally, without the need for expensive drugs, side effects, and do a lot better job anyway. It should be noted, that if we slow down in-cell production of cholesterol, then we will concurrently make more LDL receptors in make up for the lag in cholesterol production. Good right?

There are certain hormones that increase HMG-CoA activity, and certain hormones that reduce or blunt its activity (what we want). Insulin, stimulates HMG-CoA activity, and glucagon blunts it. Also of importance, insulin trumps glucagon in all cases, so an increase in insulin for whatever reason means glucagon is relegated to the red headed step child. So if we can keep insulin levels low (which they are normally without ingestion of refined sugars, grains, and high starch intake) we will make a plethora of LDL receptors that will scavenge all that nasty LDL out of the blood and keep our arteries safe.

Now this is only one part of the story, what about HDL? The good cholesterol, HDL is responsible for collecting the extra cholesterol from tissues (including atery linings) and converts this extra to LDL. So you see, it's important to still be able to get rid of the LDL when HDL is normal or high. In fact, we would like to see a shift of more HDL than LDL so that the net activity is removing extra cholesterol from tissues rather than depositing it in arteries or having it circulate looking at places to deposit it.

Now, what about all this low-fat recommendation we hear and preach (and what I was talking about in the introduction)? Remember, if we lower fat, we concommitantly lower protein intake (since protein is generally associated with fat-think animal meats, milk, etc) and since you have to give to get, low fat equals high carbohydrate. Some may argue, but you have to eat something, and a diet low in fat, is high in carbohydrates, and moderate or low in protein as well. It's just a balanced equation here, let's not get too misty eyed over this.

Most studies show that a high carb, low fat diet lower LDL (which is good right?) but also lower HDL, by an even greater percentage (uh oh!). This is bad news. How are we supposed to clean up the extra cholesterol laying around with even less HDL, and our LDL is still doing its job, floating around depositing it on arteries and such (now with even more lag time until its cleaned up by the lower HDL levels)?? What about a low carb, high fat diet (and higher protein, naturally)? We see an overall lowering of total cholesterol (although slightly less than a low fat diet), but a greater reduction in LDL cholesterol percentage-wise, and an INCREASE in HDL! So while low fat diets offer a lowering of LDL and HDL, we get the best of both worlds with low carb diets which offer a lowering of LDL and an increase in HDL. This is ultimately what will help people stave off the effects of high cholesterol (atherogenic plaques, circulatory obstructions, etc).

So the gist of it is this, high fat, high cholesterol diets won't in and of themselves make you have clogged arteries. If your carbs are restricted (say under 120g a day), and you don't have a metabolic disorder involving insulin, then your cholesterol levels will improve, and you won't have to worry about HDL, VLDL, LDL, or any other DL thing-a-ma-jig the rest of your life. So tip your glasses to whole milk....mmm mmmm good.

Pledge of Health

Alright, I'm extending this offer out to everyone and trying to rally the troops to see what kind of impact I/we can have. Take the pledge of health to start out this summer, and I promise the results will be phenomonal. Inspired by one of my clients (Jana), here it is:

I promise to abstain from dining out or eating anything with sugar for the next 30 days.

Now the sugar thing may be confusing, but in general, I mean processed foods (skim milk, low fat dairy, breads, pasta, chips, sweets, etc), not fruit. Fruit is good in moderation, and hell even green leafy vegetables have some sugar (as well as nuts, nut oils, seeds, seed oils, etc). But that's besides the point. So come on, give yourself 30 days of solid eating and see what happens!!!

Hamstrings, Lower Back, Etc...

Do you have lower back pain? Are you an athlete? Would you like to run faster, be more explosive, have better posture, and have better core strength? If you answered yes to any of these questions, then you need to stretch your hamstrings. Say what?

That's right, your hamstrings are tight (especially if you're a guy, or older, or carry around a lot of weight-muscle or not). In conjunction, your hips and quads are probably tight too. Here is a simple test for you:

Lay down on the floor with both legs flat on the ground. Try to to lift your right leg straight up as high as possible. Is it at least perpindicular (+ or - 5 degrees) to the floor? Probably not unless you are very flexible, or have seen a really good chiropractor or physical therapist lately. Second test, get back on the floor with your legs flat and together and lift your right knee towards your chest as far as possible. Then try extending your lower leg (calf and foot) straight towards the ceiling, how far can you get? If it's not very close to straight up and down, your hamstrings are tight and likely your hips are tight (check your left hip for a slight bulge when attempting this test). So why should we fix this problem and how can we do it?

Well, they why is a pretty extensive list, but here is the gist. The hamstring, acts as a brake (think of an emergency brake in a Lambo) on your leg when you are running, jumping, squatting, snatching, cleaning (not the kitchen, the exercise), or any other exercise involving lower leg extension or flexion. It literally is slowing down the movement speed, allowing for decreased force production, which we as athletes don't want. Similarly, even if we are talking about the average Joe, a tight hamstring is deleterious to normal life as a tight hamstring affects the primary movers of the spine by limiting proper activation of muscles and range of motion. You can think of the spine as having three sections. The cervical spine (C-Spine or neck), thoracic spine (which connects to your rib cage) and the more mobile lumbar spine and sacrum (lower back) which connects to your pelvis. Usually the the lower spine is the most critical part of the equation as it doesn't have anything to keep it stiff and in proper posture (slightly arched-flat back) and is prone to injury between the L4 and L5 verterbrae, and L5-S1 vertebrae. This is because the loads transferred to these parts of the spine are very high, especially when large muscle groups creating movement around this area are too tight, unbalanced, or underdeveloped (hamstrings, quads, psoas, transverse abdominis). If the average person has tight hamstrings, his gait (walking) is a series of his hamstring imposing a stress on his or her lower back, which can be alleviated by stretching. Moreover, if the average Joe is jogging or running, the stress is more profound and can lead to a clinical pathology, pain. Even worse, is if the average Joe tries to go lift some weight (gasp, heavy weight!) and cannot activate the muscles throughout a full range of motion without limitation. All of these small nuances can lead to chronic lower back pain, and are exacerbated by having a lot of weight over the front of the spine- the beer belly. So what can we do besides getting rid of the gut and working out the underdeveloped muscles to bring them up to par? We can NOT stretch!

Not stretch? What is that? It's called PNF stretching. In stark contrast to the old-fashioned static stretching that you do on your own, and feels fairly pleasant (yet is useless), PNF stretching is an active type of stretching that is the only type of stretching that can increase range of motion, lenthen muscles, and cause prolonged improvement in joint mechanics. PNF stands for proprioceptive neuromuscular facilitative stretching, which basically means we trick your brain into stretchings (err I mean not stretching) past it's normal threshold to increase the flexibility of the muscle group. This is made possible by stretching the muscle (in this instance the hamstring) to the end of its normal range of motion, and having a partner hold the leg there, while you push against the partner who is holding your leg in place for 5-10 seconds. Then the partner says relax, and momentarily stops pushing against your leg, and then pushes you a little further. They repeat this cycle 4-5 times, and voila! Mobility is increased.

Frequency is key here. For someone who is very tight, has really bad lower back pain, or wants the greatest improvement, 4-5 times a day is not unreasonable, and will yield great increases in muscle length. Similarly, once or twice per day is better than none, and will still yield some benefit.

I hope you all investigate PNF stretching as another training modality to help you achieve holistic health.

Anaerobic vs Aerobic

The other day I was watching a lecture on aerobic versus anaerobic exercise, and their respective benefits/ differences etc. I felt compelled to share and expound...enjoy.

So what is anaerobic exercise and what is aerobic exercise? Generally speaking, anaerobic exercise are exercises done at such a high intensity that the body doesn't have time to use the slow oxidative glycolyisis pathway (read: requires oxygen), but uses anaerobic glycolysis, pcr, and other lactate metabolizing pathways. Examples would be a 100yd/400m sprint, 100m row, most weightlifting activities, etc. Aerobic exercise on the other hand, is generally at a lower intensity, that can be sustained, and by definition derives most of it's energy from oxidative glycolysis, because oxygen is present and the slower energy pathway can keep up with the demand for energy from the body. Examples of aerobic exercise include a 5k run, triathalon, and less extreme exercise such as walking on a treadmill, elliptical (most likely), etc.

So these are two very different types of exercise, utilizing different energy pathways. It is because of this difference, that there are some dissimilarities between the two when it comes to adaptations. For instance, anaerobic exercise has a profound effect on bone density, it increases it greatly, especially when compared to aerobic exercise, which has little to no effect on bone density. Fat loss, yep, anaerobic exercise burns fat at a higher rate, and the fat loss continues for 12-18 hours post workout, whereas aerobic exercise stops burning fat the moment you stop the exercise. Muscle building, again, anaerobic exercise trumps aerobic exercise. Look at the body of a sprinter, they are thick, muscular and super high power. This not only comes from their weight training protocols, but also from regularly engaging in anaerobic training (sprints). Also, aerobic exercise tends to have a deleterious effect on muscle mass, that is, you will actually lose muscle mass from aerobic type workouts. This is because as you engage in these long, drawn out, aerobic sessions, your body uses protein as fuel, and adapts to become more efficient, that is, atrophied type II muscle fibers, which aren't very useful when you're pounding out the miles. Lastly, let's talk about oxidative stress, while engaging in primarily aerobic exercise, you create a bunch of free radicals (ozone, and other reactive oxygen sub-species) that can cause damage to tissues in the body. Look at the face of a master's triathalete, they look terrible and wrinkled. Thank you oxidative stress.

So why would anyone do aerobic exercise, or recommend this type of training? Well, it's easy, that's number one. Trying to get someone put in a max effort sprint, row, or dynamic weightlifting sessions (one with a set number of tasks that needs to be accomplished as fast as possible) is tough, especially if the person is new to exercise, shy about pushing their body to the limit, or has a cardio-respiritory problem. Also, everyone can go out and take a bike ride, or go for a long jog. However it takes some serious will power to run a series of 100 meter sprints, or do a max effort squat a number of times. This is the detriment of training, it's hard to get motivated to push yourself beyond what you think you can do. But the benefits of anaerobic training are vast. I know what you're thinking, doesn't aerobic exercise provide an improved cardiovascular capacity vs. anaerobic training? The answer is not really. Short, high intensity intervals, provide a better stimulus to improve AEROBIC markers of endurance (VO2max, lactate threshold/clearance, OBLA, etc). The only thing strict aerobic training has over anaerobic training, is increased exercise economy. What is that you ask?

Exercise economy is the efficiency one performs an exercise. For instance, a person who is proficient at running, is a very EFFICIENT runner. That is, they expend less energy than a novice runner. This is due to neuromuscular adaptations, energy systems adaptations, etc. At any rate, for someone who is looking to burn fat and improve body composition, rather than become an elite level runner only, this is bad news. What it means, is that the better you become at an exercise (in this case running), the less calories and energy you expel. You might become so adept at handling these aerobic challenges, that you willingly will exercise ( or run, in this case) longer and longer, because you can without getting tired. However, your fat loss will be stymied. Interestingly enough, elite level long distance runners, suck at about everything else in life besides running long distances. That is, they can't sprint, they can't lift very much weight, and can't perform a bunch of tasks in a short amount of time that require anything outside of running at the speed they train at. For instance, if I asked a world-class marathoner to do 50 bodyweight squats, 50 pullups, 50 pushups, and 50 kettlebell swings as fast as possible, and matched him/her against a person who primarily trains anaerobically (with sprints, weights, and other variables), he or she would get owned. Similiarly, the person who is fairly well trained anaerobically, would be an ok marathoner. Would the world class marathoner beat the anaerobically trained person in a marathon? Undoubtedly so, but not by as much as the anaerobically trained individual stomped the marathoner. Also, the anaerobically trained individual would only have to train hard about 20-40 minutes, 5-6 times a week. Whereas the marathoner regularly puts in 50+ miles a week of running, plus other crosstraining aerobic exercises, totalling well over 15 hrs of training a week. What do you have time for?

So, I beg you, get motivated and get some high intenisty anaerobic training going on in your life. Your bones, muscles, hormones, and face will thank you for it.