MAF Training

I hate cardio. Ok, not all cardio, but running, and any other mundane steady-state activity. Its just boring, and unless there's a good reason to do it, like competition, I see little reason to do it. It doesn't burn calories at any appreciable level for real changes in body composition (eat to lose fat, exercise for strength and performance.

I do feel that being "fit" or "in shape" means being able to exert myself aerobically and recover in a fairly short period of time, so I try to incorporate some form of aerobic exercise into my routine. As a child I loved cycling, I could just hope on my bike and take off for an hour or two at a time, speeding along, then coasting, cornering fast, zipping past people, it was fantastic. In my 20's I loved roller blading, so much so that I even got a dog-sledding harness for my dog (who loved to run so much, he's shake with anticipation every time I got out the roller blade!) And from time to time I've incorporated High Intensity Intervals Training in my programs to get cardio conditioning without having to spend more than a few (unbearably grueling) minutes at it.

As I've changed my eating habits to ketogenic, and become more educated on the Kerbs cycle (how the body converts macro-nutrients to energy), I've become interested in Optimum Fat Metabolism (OFM). I'm not an endurance athlete, and have little interest in becoming one, but the goal of further improving my bodies fat metabolism, along with it numerous benefits (I'm most interested in longevity and neurological health),means improving my aerobic base.

Aerobic energy uses fat and oxygen in the Krebs cycle, while anaerobic uses glucose and no oxygen (This is why people mistakenly believe aerobic exercise is better for losing body fat. Its a total over simplification and misunderstanding of metabolism.) Your body switches to aerobic fuel (glucose) for short, intense bursts of power, new maximum effort. Sprinting and near maximum lifts for example, which push the heart rate up above 80% of maximum. The standard rough estimate for one's maximum heart rate is 220 minus one's age (obviously, the exact number would vary depending on one's overall fitness level), for me, that number is 174 bpm. Eighty percent of that is 139 bpm.
Theoretically, once my heart rate goes over 139 bpm, I'm burning mostly glucose. Below that level, I'm burning mainly fat.

But how much work can I accomplish while staying below that level? For example, how fast can I run continuously, while staying below 139 bpm? The truth is, right now, about 8 minutes per mile, for about a minute. I can run a sub 7 minute mile in my current condition, and not feel like I'm going to die, but I would be anaerobic and not be able to sustain the level for nearly as long as if I kept in my fat burning zone.

A more highly trained endurance athlete, on the other hand, could maintain a much faster mile while still keeping their heart rate low, because they have adapted their body to more efficiently use fat. Which begs the question, what's the best method for achieving that improved adaptation?

It seems there's an upper limit to how much adaptation you can get using HIIT, and by just pushing yourself to run a little faster or a little further each time. After a point, everyone using these techniques seems to hit a limit and stop improving. That limit may be well beyond where they started, and may put them in the elite level of their sport, but not in number one place.

What I want to know is what the very top, upper echelon, number one performers are doing that other people aren't... And is it applicable to sub-elite athletes like me?

Turns out, just like nutritional ketosis, there is a little known, but growing number of athletes successfully using an alternative type of training to markedly improve their fat metabolism for endurance and it is applicable to everyone... In fact, is really pretty ease. Its called the Maximum Aerobic Function (MAF) training, pioneered by Phil Maffetone (neat how Maffetone invented MAF training, huh?)

MAF training is the "low and slow" of exercise. The premise is simple: Exercise for a given period of time right at your ideal aerobic heart rate, maintaining a pace that allows you stay right on target for the entire training session. Period. That's it.

As your heart gets more fit, the exact pace needed to maintain that heart rate will increase. You'll adapt so your previous pace is easy and be forced to increase speed.

I set myself the goal of doing a Spartan race next spring, which is a 10K obstacle course. I'll have to run, and I know myself, I will not want to be dead last, so this gives me motivation to train my aerobic base.

The other reason for doing this is to improve my lifting. Weight lifting is mainly anaerobic, but by improving my aerobic base, I'll spend less time in an anaerobic state, between lifts, digging into my glucose reserves less and allowing my to continue to get stronger while maintaining a ketogenic lifestyle. Those are my goals, now how to go about it.

First is using a heart rate monitor. This is non-negotiable. You cannot possible know your heart rate without one. If you think you can, try one session of MAF using one and you'll see how wrong you are. Sometimes, walking up a hill feels easy, but your heart rate shoots up. Or you'll be jogging at a nice steady pace, thinking your doing fine, and look down and BAM! you're heart rate is 15 bpm too high, even though your not even winded!

To get my target heart rate, I subtract an additional 40 from my max heart rate (or 180 minus age). In my case, its 134 bpm, a little under the 80% threshold, is my upper limit target. I subtract another 10 from that and get my lower limit threshold, 124 bpm.

After a good 10 to 15 minutes of warming up with light exercise, walking or riding my bike at an easy, sub 124 bpm pace, I begin. I jog lightly until my heart rate hits 134, then I slow to walk until it drops to 124, then I job again. Job, walk, jog, walk, rinse and repeat for up to 30 minutes. Then cool down.

Jogging through my Atlanta neighborhood hills, I get to see exactly how much various inclines at various paces affect my heart rate. It becomes a game to see if I can find the right pace to stay in my zone for an extended period of time as the terrain changes and I get further along.

Every month, Maffetone recommends doing a test. Using a set course, or time limit on a flat track, test your pace while maintaining your heart rate zone. Always use the same course or time, so you know the conditions are the same. Each month, you should see improvement as your aerobic base improves.

I did my first test this week, even though I've been using this system for a few weeks. I'll know for sure next month if I'm improving, but I can already see improvements in my performance and how I feel.

Since I hate steady state cardio, this has given me something more interesting to focus on, making it more enjoyable. Once I get my "new" bike (read as "the $45 used bike I bought and have to rebuild) working, I'll alternate between running and biking. Biking is my preferred method, but the position is hard on my back, and running is more appropriate to train for the Spartan Run.

I'll begin incorporating a couple of HIIT sessions a month, to get those benefits, plus train my body to respond to the need to sprint suddenly. But I'll wait a few months for that, to get a solid base of aerobic performance first.

I'm doing this kind of training 3-5 times a week. Either first thing in the morning, or immediately following a lifting session. Never immediately before lifting. I have also begun wearing the heart rate monitor during my lifting, to see where my heart rate is while I work out. It obviously fluctuates a lot more than while jogging, but I can see how fast my heart rate drops from its peak back to aerobic which is interesting.

I'll post again when I do my next test to see how this is all working out.

Adventures in Keto, Part 5 - Retox

A couple of weeks ago, I went on vacation to Jamaica, at an all inclusive resort. If you haven't been to such a resort, its sort of like being on a cruise ship. Just about anything you want to eat or drink is included in the price. There are multiple bars and restaurants on the property, with different themes and styles of food to choose from. Which all sounds really great. But for someone trying to live low carb, it presents quite a challenge. I knew going in that it would be difficult to maintain my preferred eating habits while on vacation, and I was prepared to make some exceptions. By the second day it had become clear that unless I was willing to severely limit my self, it would be impossible. Breakfast was the easiest meal, because there was an extensive buffet, with plenty of eggs and bacon and cheeses and cured meats and salmon, etc. But once lunch and dinner came around, the keto-friendly options declined. By the end of the second night, I decided to just stop worrying about it and indulge myself while on vacation. I was there to relax, so why stress about food? (Also, as a member of the service industry who has spent years in and around high end restaurants, it was obvious that the staff was less experienced and knowledgeable than I am used to, and I honestly didn't want to be "that guy" making their jobs more difficult. Americans already have a well deserved reputation abroad for being entitled and difficult, and not eating my preferred way was not going to kill me -- at least not in the short term.) And indulge I did. There was a "sweets deli" which was essentially a dessert shop with ice cream and cookies and cakes and candies. The selection changed at least twice during the day, and varied throughout the week. I was delighted to discover a number of delicious chocolate treats, which I enjoyed to my hearts content. I did notice some of my high-carb symptoms returning almost immediately. Mid-afternoon sleepiness was the main one, along with an overall reduction in my focus and energy. One afternoon I was ravenously hungry, and began to feel light headed and weak, and my hands started shaking. I happened to be in my hotel room at the time, so I did a quick blood sugar test (yes, I packed my meter). The reading was 55, which is very low. Even in full ketosis, my readings are usually between 70 and 80. I had to eat something to bring my body back into balance. I hated the feeling of being a slave to food again. Its odd to hear myself say that, because I've never been over weight. I've always been someone people view as being fit and healthy. But after months of not having to eat on a schedule, I realize that anyone who isn't fat adapted is constantly reminded by their body that they need to eat. When I'm fat adapted, I eat when I'm ready, not when my body demands it, I'm in control. It surprised me how quickly my body became dependent on carbohydrates again. I had not expected that. I figured once I got home, I'd get back to eating right and withing a couple days, all would be well again. I was wrong. After months of feeling great and seeing a steady decline in my cravings for sweets and carbs, and rarely feeling hungry, all those things returned. I've been home for over two weeks now, back to eating healthy, low carbs, high fat, moderate protein and feeling better. But I did have to go through a less intense transition period again, complete with lethargy and cravings. Since transitioning back, I still am battling hunger pangs and sugar cravings. When I started eating low carb back in October, I knew it would take awhile for the cravings and other carb addiction symptoms to abate, but I didn't think I'd have to go through that a second time after only a week off my diet. Back then I was prepared, so I could handle it. This time, I wasn't mentally prepared, so its been difficult, and I've screwed up a couple times, which only drags the whole process out longer. Now that I've realized this is how it is, I'm buckling down and getting serious. I know I want to live better, to feel better, to have all the benefits I enjoy from eating right. I screwed up by going off the diet and now I have to do the work to get back where I want to be. I'm not beating myself up, don't get that impression. Its more of a mental shift, of realizing that until my body adjusts back, I have to be vigilant about not indulging my cravings, of recognizing when I'm actually hungry and when I'm just bored, and when I'm making excuses (like yesterday at my friends birthday, when I drank wine and sugary Margaritas and totally put myself out of ketosis.) Over the previous months of living low carb, I've been able to have an occasional sugary treat and return to ketosis easily. What I can't do is spend a week eating carb loaded foods and expect to just pick up where I left off. I learned a lesson about how my body works and what I can and can't do. Eating a lot of carbs makes me feel less than great, and feeling great is my new normal. I wonder how I went through life for so long accepting that as normal. This experience has made me very aware of how what I eat impacts my body and my life. My sleep, my mood, my energy, my mental focus and clarity, all of which go on to impact my relationships, my work, my enjoyment of life in general. When I'm eating right, my whole life is better, its just that simple. I have another trip coming up in a couple months, my fourth trip to Burning Man. Fortunately, at Burn one has to bring all your own food, so I can maintain my healthy eating there with some planning.

Dry Aged Beef -- At Home!

Dry aged beef is amazing. If you love steak, you owe it to yourself to try it. But do you want to pay for it? Probably not.

Two weeks ago, I had dinner out with friends, and saw a 35 day dry aged rib eye on the menu for $50. Given the quality of the restaurant we were in, I was really tempted. But I also know a fair amount about cooking, and what it takes to cook streak so its really tasty (dry aged or not), and decided, it wasn't worth it. I can cook a better rib eye than most restaurants at home, honestly. But...

How hard is it to age a steak yourself?

After reading The Food Lab, by J. Kenji Lopez-Alt, it turns out its not that hard. An internet search found several accounts of other people doing it, with very similar processes, so I decided to give it a try.

In my research I discovered there's a thing called wet-aging, too. Basically, its bullshit. Don't pay for it, it does little to nothing for flavor. Moving on...

So, how do you do it?

EQUIPMENT:

Mini-Fridge -- You can skip this, but not recommended. Aging meat will give out strong aromas which other food can pick up, and it pick up flavors from other foods. Plus, using your household refrigerator with the door opening and closing all day does not provide a stable environment. I found a used mini-fridge on Facebook Marketplace for $20. If the steak thing doesn't workout, I can still use the fridge.

Wire rack -- This is to make sure the meat gets full circulation on all sides. In my case, the wire shelf in the fridge works fine.

Small Fan -- Well, maybe. Several sources recommend it. I bought one, and decided not to use it because the fan itself produced too much heat for the fridge to keep cool enough. More on that Below.

Thermometer -- This is critical. The meat must be held between 32°F and 40°F. Too cold and the meat with freeze, which stops the enzymatic processes we want, and too warm it it will spoil. I bought a cheap refrigerator thermometer to keep in the fridge to make sure it's consistent. I already owned an Infra-Red thermometer gun and a Thermopen instant read, which I used to check the fridge more accurately before starting (more below). You can probably get away with just one. If that's your choice go for the most accurate you can get.

Meat - Because the aging process drys out the outer layer of meat, you want to start with a good sized piece. When its done, you'll cut away the dry layer. The bigger your piece to start, the more finished product.  I bought a Prime grade rib roast, with 3 ribs, with the fat cap still on. The official name for this cut is "109A." When its done, it can be cut into rib eye steaks. The more fat the better, because the fat will dry out, and end up being cut away at the end.

That's it! Now on to the fun!

PROCESS:

Before I bought my meat, which wasn't going to be cheap, I decided to check the fridge was working as I needed it.  I spent a couple days letting it run while empty and checking the temp. Using the IR thermometer and fridge thermometer I got it dialed into my ideal temperature range (32°F to 40°F).

With the IR gun, I found that the temperature varied in different parts of the interior, so I adjusted until all areas were at least below 40°F after a few hours with the door closed. I also noticed that the fridge thermometer was reading at the bottom of the "ideal" range. As long as it stays consistent, that's fine.

I installed a small computer fan, to try to improve air circulation and get a more even temperature. But after a day, the internal temp of the fridge was consistently above 40°F, even when set to "MAX". This was no good.

Placing my had in front of the fan, I found it was blowing warm air. The fan motor was generating too much heat for my tiny fridge to keep up with, so I removed it. If the fridge was bigger, I suspect the fan would be a good idea, but since its about as small as they come, I think its fine without.

Once I was satisfied the fridge would maintain a safe temperature, I bought the meat. When I got it home, I unwrapped it and dried it off. Using paper towels, I patted all the excess liquid and got it as dry as I could.

Straight from the butcher's shop, 7.56 pounds of Prime Rib Roast.

 Then came the hard part: I put the hunk of meat on the shelf in the fridge and closed the door.

Day 1: In it goes.
Note: The temp on the thermometer is too high, because I kept the door open too long to take pictures.

That's it. Done. Now wait 6 weeks. Well... Sort of.

After 1 day I checked the meat and temperature. The meat looked a little redder, some juices had dripped onto the bottom of the fridge. The fridge thermometer continued to read the same as during testing. The IR gun gave different readings all around the interior, all within range. The surface of the meat itself read 35°F. Perfect!

Next I inserted my instant read thermometer, to get the internal temperature of the meat. This is really the most important part. The outside will dry out and protect the rest over the first week or two, so its the internal temperature that needs to be consistent. It read 32°F, right at the lower edge of ideal. I turned up the fridge temp a bit and closed the door.

The next day I performed the same checks. the interior of the meat now read 34°F. Happy with this, I closed the door and will leave it alone for awhile. My plan is to turn the meat once a week, checking the temp at the same time. Turning will help ensure even circulation of air, and promote even drying.

How long?

This is the interesting part, especially if you're willing to pay for an aged steak at the butcher's or in a restaurant. During the first two weeks, aging does nothing for flavor. As the enzymes inside the meat go to work, they will tenderize the meat, but not impart much flavor. I personally would not pay the prices for meat aged this little. If I want more tender meat, I'll buy a different cut.

Flavor changes begin to happen around three weeks and get more intense as you go, with four to six weeks being most people's ideal range. After six weeks, I'm told the flavors get really, really intense and most people find them overwhelming.

Most restaurants who sever dry aged beef stay in the 28-35 day range, which is four to five weeks. Those are aged by professionals in purpose designed, highly controlled conditions. Since I don't have those conditions, and most sources I found for home aging recommended six weeks, that's what I'm shooting for.

One Week

After 1 week, the meat looks a darker and kind of weird, but the internal temperature is perfect.

I flipped it over to ensure even drying all around. I also relocated the thermometer so its not directly beneath the cooling unit. 

Week Two

Flipped it back over. Internal temperature still a consistent 35°F (again the thermometer in the photo is wrong because the door was open for a few minutes to clean up some of the blood that dripped and dried.)

14 days after starting and the outside of the meat is totally dry. Handling it to flip it again it was hard and leathery. It looks pretty rough. The surface temp is 39°F and the internal temp is 35°F, so I'm right in the sweet spot.

What looks like white salt crystals are forming on the outside of the meat. I think that may be fat, but I'm not sure, since it looks different from the fat cap.

I expected to get some odors or bad smells, but so far nothing. Which I think means it not rotting, it doesn't seem to be, there are no gray areas. I'll check it again next week.

Week Three

Three Weeks: its really dark now, Purplsh-brown, almost black, no odor. 

By week three, the last bits of the dark red seem to have vanished and its really dark purplish-brown. There's no odor.

Week Four

Week Four: Not much change in appearance from last week.

Four weeks now, two-thirds of the way there! Visually, it looks pretty much the same as last week. I flipped it again to ensure even circulation, but at this point I'm not sure its necessary. The outer layers are tough and leathery and dry. 

Temperatures are remaining consistent. The prod from the thermometer slips easily into the tough looking meat, and read 35°F still, which is perfect.

I didn't notice any smell when I opened the fridge so I got close and sniffed. There's a light, almost chocolate aroma coming from the meat, which I didn't expect. Its now 28 days aged, and could be cooked and served, but the real flavor is only just beginning to develop now, so I'm going to give it more time.

Week Five

Week Four: Not much visual change since last week.

Almost ready! Its now 35 days aged, a perfectly acceptable age for severing, but I want to go a little longer. The chocolaty aroma I smelled last week is a little stronger, but only right after I open the door. The smell is not at all unpleasant, and not as cheese-like as I expected. 

Next week we carve it up!

Week Six

Today the meat is done! Forty-two day dry-aged rib eye steaks! 

Visually, not much change from last week. There is still almost no aroma when opening the mini-fridge. The steak feels leathery and a bit greasy. Poking the meatiest parts, it feels tough like jerky.

Six Weeks: all ready to carve up!

Before trimming and carving, I weighed the roast. When I bought it, it weighed 7 lbs 9 oz (3.43Kg). After six weeks of aging, it came in at 6 lbs 2 oz, a net lose of 1 lb 7 oz in moisture. 

But it's going to get lighter. All that tough, dried outer shell needs to come off. I'm not a butcher, so my trimming was probably not the most expert thing, but with a boning knife and a chef's knife, I carved away the tough outer fat and meat in thin slivers, so as not to take off too much edible meat. It wasn't difficult. 

When I was pretty sure I'd gotten down to the good stuff. It looked like a lot! 

The scraps after trimming the roast.

The trimmed roast, doesn't look too different from a normal rib roast now. 

 Once again, I weighed the beast. Now it was down to a lean 4 lbs 15 oz, a total lose of 2 lbs 10 oz from when I bought it. Now I understand one reason dry aged steaks are so expensive! By weight alone, based on my purchase price, value per pound jumped 158%.

I divided the roast into three bone-in steaks, each about 2" thick. They weren't perfectly uniform since the end pieces had more meat trimmed off them.

Once divided into steaks, you can really see the color of the inside -- its a nice purple with some brown areas. But there's no rotting smell at all, so all good.

Each bone-in steak was about 2 pounds, that's a lot of meat! I'm not one of those ultra macho guys who eats tons of steak in one sittings, there's no way I could eat a whole of in a single sitting, and the idea of reheating left over dry-aged steak makes me cringe. So I de-boned one and cut into two boneless rib eyes, each about an inch thick. 

Boneless dry-aged rib eye steaks. I decided to cut off a that big chunk of fat at the bottom after taking this photo.

Once all the steaks were carved up, I vacuum sealed them in individual bags. The boneless steaks went immediately into the sous vide to cook up medium-rare. Once sous vide, they'll store for months! (Though I'll probably eat them all in a week.)

One of the bone-in steaks will get cooked up tomorrow night to share with a friend of mine who paid for half the experiment, and the other is hers to keep.

All told, I spent about $1.43 per ounce to produce these delicious dry-aged steaks (not counting the one-time cost of $20 for the used mini-fridge). Last week I was at a fine local restaurant that was offering an 12 oz, 42 day dry-aged steak for $65, or $5.41 per ounce, nearly four times my cost. 

Regardless of the initial expense, this was super easy to do, and from a cost stand point, totally worth it!

For Next Time?

I will absolutely do this again! But with a couple changes. I did a little hunting around and found I can get full, grass fed, rib roasts shipped for about $225. That's a lot more cost effective, being about twice the meat for only about $40 more than I paid this time. That would dramatically increase the value of this whole process.

I could probably find even less expensive if I skipped the grass-fed part, but why bother? Grass-fed tastes better, is healthier to eat, and less cruel to the cows. 

A full roast won't fit in my mini-fridge, but I can probably get 5 ribs worth in, instead of just three (Maybe even six? I'll measure when I get it.) The remaining ribs can be divided up and eaten during the six weeks of aging, so I'll always have good steaks in the house, just not always aged. 

The other thing I'm going to do is try to increase the temp of the fridge a little. I think if I get the internal temp of the meat up a couple degrees, I'll get a little more aging flavor. As long as I keep it below 40°F, it should be fine. 

Oh Yeah, How Do They Taste?

Cooking up a dry aged steak is done the same as cooking a normal steak, but it feels different. Because the meat has far less water in it, it doesn't pop and sizzle like you expect in the pan. It does develop a very nice crust though, because it still has all the fat.

I cooked one up in a cast iron pan, my preferred method for rib eye, and it was delicious. The texture is dryer, and chewer, again because it lacks water. But the taste is delicious.

Another steak I sous vide, then finished in a pan. This method ensures perfectly to temperature steak, and it was just as delicious.

For me, I won't say dry aged is better than regular steaks, only different, and the price of buying a properly dry aged steak from a butcher or restaurant aren't worth it for me. But with this method, I will absolutely do it again.