Body2build

by Lyle McDonald, CSCS

Introduction

As the Cyclical Ketogenic Diet (CKD) becomes more popular among natural bodybuilders, a great many questions have arisen regarding any and all manners of topics. One of the primary has to do with exercise on a CKD. First and foremost, individuals want to know what types of exercise can and can not be sustained on a CKD. Secondly questions arise as to what is the optimal training structure to maximize either fat loss or muscle gains on a CKD.

To answer these two questions, a lot of topics have to be covered ranging from exercise biochemistry to the hormonal response to different types of exercise to the implications of a diet which does not contain

carbohydrates during the week. The goal of this article will be to discuss the CKD primarily for fat loss. For reasons beyond the scope of this article, the CKD is most likely not the optimal diet for mass gains.

What is the CKD?

The Cyclical Ketogenic Diet, CKD, is a general term to describe diets such as The Anabolic Diet (by Dr. Mauro DiPasquale) and BODYOPUS (by Dan Duchaine). While there are many variants, the most common structure for a CKD is 5-6 days of strict low carbohydrate eating (less than 30 grams per day) with a 1-2 day carb-loading period (where carbohydrate intakes is roughly 60-70% of the total calories consumed). The idea behind the CKD (which will be discussed in a later article) is to force the body to burn fat during the lowcarb days, while sustaining exercise intensity by refilling muscle glycogen stores during the weekend carb-load.

Some Basic Exercise Metabolism

To better understand the effects of a CKD on exercise performance, we have to look briefly at how different forms of exercise affect fuel utilization in the body. There are four potential fuels which the body can use during exercise: glycogen, fat, protein and ketones. Except under certain conditions (which will be mentioned when necessary), protein and ketones do not provide a significant amount of energy during exercise. Therefore this discussion will focus primarily on glycogen and fat use during exercise. To simplify this article, exercise will be delineated as either aerobic or anaerobic (which will include interval training and weight training).

Aerobic Exercise

Aerobic exercise is generally defined as any activity which can be sustained continuously for periods of at least three minutes or longer. Examples would be walking, jogging, cycling, swimming, aerobics classes, etc.

The primary fuels during aerobic exercise are carbohydrate (muscle glycogen and blood glucose) and fat (from adipose tissue as well as intramuscular triglyceride) (1,2). At low intensities, fat is the primary fuel source during exercise.

As exercise intensity increases, less fat and more glycogen is used as fuel. At some intensity, sometimes called the "Crossover point", glycogen becomes the primary fuel during exercise. (3) This point corresponds roughly with something called the lactate threshold. The increase in glycogen utilization at higher intensities is related to a number of factors including greater adrenaline release (3,4) decreased availability of free fatty acids (5), and greater recruitment of Type II muscle fibers (3,6,8). The ketogenic diet shifts the crossover (i.e. lactate threshold) point to higher training intensities (3) as does regular endurance training (4).

Under normal (non-ketotic) conditions, ketones may provide 1% of the total energy yield during exercise (8). During the initial stage of a ketogenic diet, ketones may provide up to 20% of the total energy yield during exercise (9). After adaptation, even under conditions of heavy ketosis, ketones rarely provide more than 7-8% of the total energy yield which is a relatively insignificant amount (10,11,12).

Generally, protein use during aerobic exercise is minimal, accounting for perhaps 5% of the total energy yield. With glycogen depletion, this may increase to 10% of the total energy yield, amounting to the oxidation of about 10-13 grams of protein per hour of continuous exercise (14). This is at least part of the reason that excessive aerobic exercise, especially under low glycogen conditions, can cause muscle loss while dieting.

Studies on ketogenic diets (2 to 6 weeks) find a maintenance (15, 16) or increase (17,18) in aerobic endurance during low intensity exercise (75% of maximum heart rate and below). At higher exercise intensities (around 85% of maximum heart rate which is likely above the lactate threshold), as glycogen use increases, performance decreases on a ketogenic diet (19).

Anaerobic Exercise

While anaerobic exercise refers generally to any activity which lasts less than three minutes or so, most individuals are interested in the effects of a CKD on weight training. However athletes involved in sports such as sprinting, or any activity lasting less than three minutes, will have the same considerations discussed in this section.

Weight training refers to any activity involving the use of heavy resistance which lasts less than three minutes (i.e. it is anaerobic). Weight training is slightly more complicated to discuss in terms of fuel use than aerobic exercise. For very short activities (less than 20 seconds), muscles use ATP (adenosine triphosphate) which is stored directly in the muscle. Activities lasting greater than 30 seconds will rely on the breakdown of glycogen (carbohydrate stored in the muscle). During anaerobic exercise, fat can not be used directly as a fuel (1).

Relatively few studies have examined the effects of carbohydrate depletion on resistance training. In fact no studies have studies the effects of a ketogenic diet on weight training performance. However since weight training can only use glycogen for fuel, we can logically conclude that carbohydrates are critical for weight training performance. In fact, this is the primary reason to insert the carb-loading phase of the CKD on the weekend: to sustain high intensity exercise performance while still deriving the benefits of ketosis. Other issues pertaining to glycogen levels and depletion appear below.

The Hormonal Response to Exercise

The hormonal response to exercise is important from two standpoints. First and foremost, manipulation of the type of exercise done on a CKD can affect how efficiently fat loss or muscle gain occur. Second, to most rapidly enter ketosis (which requires a depletion of liver glycogen), certain types of exercise will be more effective than others. The primary hormonal response to both aerobic and anaerobic exercise are discussed below.

There are several hormones which are affected by aerobic exercise depending on exercise intensity and duration. They primarily impact on fuel utilization.

Catecholamines:

Adrenaline and noradrenaline are both involved in energy production. The catecholamines raise heart rate and blood pressure, stimulate fat breakdown (lipolysis), increase liver and muscle glycogen breakdown, and inhibit insulin release from the pancreas (20). Both adrenaline and noradrenaline increase during aerobic exercise although in differing amounts depending on intensity of exercise. Noradrenaline levels rise at relatively low exercise intensities stimulating FFA utilization in the muscles but relatively low levels of liver and muscle glycogen breakdown.

Insulin:

During aerobic exercise, insulin levels drop quickly due to an inhibitory effect on it’s release from the pancreas by adrenaline (20, 21). The drop in insulin allows free fatty acid release to occur from the fat cells during exercise. Lowering insulin is also important for establishing ketosis. Despite a decrease in insulin levels during exercise, there is an increased uptake of blood glucose by the muscle. An increase in glucose uptake with a decrease in insulin indicates improved insulin sensitivity at the muscle cells during exercise.

Glucagon:

As the mirror hormone of insulin, glucagon levels increase during aerobic exercise (20). Thus the overall response to aerobic exercise is pro-ketogenic in that it causes the necessary shift in the Insulin/Glucagon ratio to occur.

Thus the overall response to aerobic exercise is to decrease the use of glucose and increase the use of free fatty acids for fuel. This is beneficial from the standpoint of establishing ketosis, as will be discussed in greater detail below.

Weight training affects levels of many hormones in the human body depending on factors such as order of exercise, loads, number of sets, number of repetitions, etc. The primary hormones we are interested in which are affected by weight training are the androgens (primarily testosterone, growth hormone and IGF-1. With the exception of testosterone, the hormonal response to weight training primarily affects fuel availability and utilization (22).

Growth hormone (GH):

GH is a peptide hormone released from the hypothalamus in response to many different stimuli including sleep and breath holding (23). Although growth hormone is thought to be muscle building, at the levels seen in humans, it’s main role is to mobilize fat and decrease carbohydrate and protein utilization (24).

The main role of GH on muscle growth is most likely indirect by increasing release of Insulin-like Growth Factor 1 (IGF-1) from the liver (24). The primary stimulus for GH release with weight training appears to be related to lactic acid levels and the highest GH response to training is seen with moderate weights (~75% of maximum), multiple long sets (3-4 sets of 10-12 repetitions, about 40-60 seconds per set) with short rest periods (60-90 seconds). Studies using this type of protocol (generally 3X10 Rep maximum with a 1′ rest period) have repeatedly shown increases in GH levels in men (25, 26) and women (27,28) and may be useful for fat loss due to the lipolytic (fat mobilizing) actions of GH. Multiple sets of the same exercise are required for GH release (28).

Testosterone

Testosterone is frequently described as the ‘male’ hormone although women possess testosterone as well (at about 1/10th the level of men or less) (4).

Testosterone’s main role in muscle growth is by directly stimulating protein synthesis (23,29). Increases in testosterone occur in response to the use of basic exercises (squats, deadlifts, bench presses), heavy weights (85% of maximum and higher), multiple short sets (3 sets of 5 repetitions, about 20-30 seconds per set) and long rest periods (3-5 minutes). Studies have found a regimen of 3X5 rep max. with 3′ rest to increases testosterone significantly in men (25,26,30) but not in women (27). It is unknown whether the transient increase in testosterone following training has any impact on muscle growth.

Insulin like growth factor 1 (IGF-1)

IGF-1 is a hormone released from the liver, most likely in response to increases in GH levels (31). However the small increases in GH seen with training do not appear to affect IGF-1 levels (32). More likely, IGF-1 is released from damaged muscle cells (due to eccentric muscle actions) and acts locally only to stimulate growth (33,34).

Exercise and Ketosis

In that ketosis indicates that the body has shifted to using fat as it’s primary fuel, and since only five to six days exist per week to be in ketosis, a question which arises is how to most quickly establish ketosis.

Aerobic and anaerobic exercise have somewhat differential effects on ketosis and are discussed here.

It has been known for almost a century that ketones appear in higher concentrations in the blood following aerobic exercise (35). The overall effect of aerobic exercise below the lactate threshold is to induce or enhance ketosis. Liver glycogen decreases, insulin decreases, glucagon increases and there is an increase in free fatty acid levels in the bloodstream.

Aerobic exercise can quickly induce ketosis following an overnight fast. One hour at 65% of maximum heart rate causes a large increase in ketone body levels but the ketones do not contribute to energy production to any significant degree (36). 2 hours of exercise at 65% of maximum heart rate will raise ketone levels to 3mM after 3 hours. High levels of ketonemia (similar to those seen in prolonged fasting) can be achieved five hours post-exercise (36).

During high intensity exercise, the same overall hormonal picture described above occurs, just to a greater degree. Adrenaline and noradrenaline both increase during high intensity activities (both interval and weight training). The large increase in adrenaline causes the liver to over-release liver glycogen raising blood glucose (4,20). While this may impair ketogenesis in the short term, it is ultimately helpful in establishing ketosis initially. Insulin goes down during exercise but may increase after training due to increases in blood glucose. Glucagon goes up also helping to establish ketosis. Probably the biggest difference between high and low intensity exercise is that free fatty acid release is inhibited during high intensity activity, due to the increases in lactic acid (5).

Glycogen Levels and Depletion

To understand how to optimize training for a CKD, a discussion of glycogen levels under a variety of conditions are necessary. As well, some estimations must be made in terms of the amount of training which can and should be done as well as how much carbohydrate should be consumed at a given time.

Muscle glycogen is measured in millimoles per kilogram of muscle (mmol/kg). An individual following a normal mixed diet will maintain glycogen levels around 80-100 mmol/kg. Athletes following a mixed diet have higher levels, around 110-130 mmol/kg (37). On a standard ketogenic diet, with aerobic exercise only, muscle glycogen levels maintain around 70 mmol/kg with about 50 mmol/kg of that in the Type II muscle fibers (38,39).

Fat oxidation increases, both at rest and during aerobic exercise around 70 mmol/kg. Below 40 mmol/kg, exercise performance is generally impaired. Total exhaustion during exercise occurs at 15-25 mmol/kg. Additionally when glycogen levels fall too low (about 40 mmol/kg), protein can be used as a fuel source during exercise to a greater degree (14).

Following total depletion, if an individual consumes enough carbohydrates over a sufficient amount of time (generally 24-48 hours), muscle glycogen can reach 175 mmol/kg or higher (38). The level of supercompensation which can be achieved depends on the amount of glycogen depleted (40,41). That is, the lower that muscle glycogen levels are taken, the greater compensation will be seen. If glycogen levels are depleted too far (below 25 mmol/kg), glycogen supercompensation is impaired as the enzymes involved in glycogen synthesis are impaired (42). A summary of glycogen levels under different conditions appears in figure 1.

Figure 1: Summary of glycogen levels under different conditions

Condition Diet Glycogen

level (mmol/kg)

48 hour carb-up High carb 175

36 hour carb-up ~150

24 hour carb-up ~120-130

Athlete Mixed diet 110-130

Normal individual Mixed diet 80-100

Normal individual, Ketogenic diet 70

Aerobic exercise only

Fat burning increases 70

Exercise performance decreased 40

Exhaustion 15-25

Glycogen Depletion During Weight Training

Having looked at glycogen levels under various conditions, we can now examine the rates of glycogen depletion during weight training and use those values to make estimations of how much training can and should be done for the CKD.

Very few studies have examined glycogen depletion rates during weight training. One early study found a very low rate of glycogen depletion of about 2 mmol/kg/set during 20 sets of leg exercise (43). In contrast, two later studies both found glycogen depletion levels of approximately 7-7.5 mmol/kg/set (44,45). As the difference between these studies cannot be adequately explained, we will assume a glycogen depletion rate of 7 mmol/kg/set.

Examining the data of these two studies further, we can estimate glycogen utilization relative to how long each set lasts. At 70% of maximum weight, both researchers found a glycogen depletion rate of roughly 1.3 mmol/kg/repetition or 0.35 mmol/kg/second of work performed (44,45).

Rates of glycogen depletion during weight training at an intensity at 70% max

Depletion per set 7.5 mmol/kg/set

Depletion per repetition 1.3 mmol/kg/rep

Depletion per second of work 0.35 mmol/kg/second

Designing the Workout

With all of the above information presented, we can go through the steps to develop a CKD workout for fat loss. The goals of the workout are:

1. Deplete muscle glycogen in all bodyparts to approximately 70 mmol/kg by Tuesday as this will maximize fat utilization by the muscles but will not increase protein utilization.

2. Maximize Growth Hormone output (which is a lipolytic hormone) on Mon/Tue with a combination of long sets, multiple sets, and short rest periods.

3. Maintain muscle mass with tension work outs on Monday and Tuesday.

4. Deplete muscle glycogen to between 25 and 40 mmol/kg on Friday to stimulate optimal glycogen supercompensation.

5. Stimulate mass gains during the weekend of overfeeding with a full body tension workout (a high rep depletion workout is also an option)

6. Use cardio to quickly establish ketosis and enhance fat loss

The primary goal that still needs to be discussed is how much training is necessary to achieve goals #1 and #4.

We will assume a lifter has completed a 36 hour carb-up, ending Saturday evening, with a muscle glycogen level of 150 mmol/kg in all major muscle groups. To deplete to 70 mmol/kg in the first two workouts, this person needs to deplete:

150 mmol/kg – 70 mmol/kg = 80 mmol/kg of total glycogen.

Using the rate of glycogen depletion listed above we see that

80 mmol/kg divided by 1.3 mmol/kg/rep = 61 total reps.

or

80 mmol/kg divided by 0.35 mmol/kg/sec = 228 seconds of total set time.

Assuming an average set time of 45 seconds (10-12 reps at 4 seconds per repetition) this level of glycogen depletion would require approximately 5-6 sets per bodypart.

For the Friday workout, our lifter now wants to deplete muscle glycogen to between 25-40 mmol/kg before starting the carb-up. This would require a further glycogen depletion of

70 mmol/kg – 25 mmol/kg = 45 mmol/kg

70 mmol/kg – 40 mmol/kg = 30 mmol/kg

30-45 mmol/kg.

This would be

30-45 mmol/kg divided by 1.3 mmol/kg/rep = 20-30 reps

30-45 mmol/kg divided by 0.35 mmol/kg/second = 85-128 seconds.

The CKD Workout Routine

With the above estimations for sets and reps having been made, we can develop a sample workout routine. The format for the CKD week is:

Day Workout type Diet

Sunday: 30′+ of low intensity cardio in Ketogenic

morning to establish ketosis

Monday: Tension weight training workout Ketogenic

Tuesday: Tension weight training workout Ketogenic

Wed/Thu: cardio optional for fat loss Ketogenic

Fri: Full body workout Ketogenic prior to workout

Begin carb-load after

workout

Saturday: No workout Carb load

Sample workouts appear below.

Mon: Legs and abs

Exercise Sets Reps Rest

Squats 4 8-10 90"

Leg curl 4 8-10 90"

Leg extension OR 2 10-12 60"

feet high leg press

Seated leg curl 2 10-12 60"

Standing calf raise 4 8-10 90"

Seated calf raise 2 10-12 60"

Reverse crunch 2 15-20 60"

Crunch 2 15-20 60"

Total sets 24

Tue: Upper body

Exercise Sets Reps Rest

Incline bench press 4 8-10 60"

Cable row 4 8-10 60"

Flat bench press 2 10-12 60"

Pulldown to front 2 10-12 60"

Shoulder press 3 10-12 60"

Barbell curl 2 12-15 45"

Triceps pushdown 2 12-15 45"

Total sets 20

There are two options for the Friday workout. One is to perform a tension workout to stimulate growth during the carb-load. The second is to do a high-rep depletion workout, which should be done in circuit fashion solely to deplete muscle glycogen.

Sample Friday tension workout:

Exercise Sets Reps Rest

Leg press 3 8-10 90"

Leg curl 1 10-12 60"

Calf raise 2 10-12 60"

Bench press 3 8-10 90"

Wide grip row 3 8-10 90"

Shoulder press 1-2 10-12 60"

Undergrip pulldown 1-2 10-12 60"

Total sets 14-16

Sample circuits for Friday depletion workout:

leg press, dumbbell bench press, cable row, leg curl, shoulder press, overgrip pulldown, calf raise, triceps pushdown, barbell curl, reverse crunch.

leg extension, incline DB bench press, narrow grip row, seated leg curl, lateral raise, undergrip pulldown, seated calf raise, close grip bench press, alternate DB curl, twisting crunch.

squat, flat flye, cable row, standing leg curl, upright row, overgrip pulldown, donkey calf raise, overhead triceps extension, hammer curl, crunch.

Since the intensity is lower (roughly 50-60% of maximum) glycogen depletion per set will also be lower. Additionally, 20 reps will only require about 20-40 seconds to complete. Assuming glycogen had started at 70 mmol/kg, it will likely take 4-5 circuits to fully deplete glycogen.

Perform 10-20 quick reps per set (1 second up/1 second down). Take 1′ between exercises, and 5′ between circuits. The sets should not be taken to failure; the goal is simply to deplete muscle glycogen. Many trainees complain of nausea during this workout, which is caused by not resting long enough between sets.

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References

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In recent media, low carbohydrate diets have been THE fad for almost everybody in America wanting to lose weight. From your secretaries, elementary school teachers, and desk clerks, to bodybuilders, models, actresses, and athletes.

However, there is a huge difference between those who follow an Atkins plan and those who follow a cyclical ketogenic diet (CKD). Atkins is a low carb plan for those who are quite sedentary, walk maybe 3 times a week at the most, and just follow normal everyday activities. So forget Atkins here. The CKD is for those who’s main concern is true fat loss and muscle preservation—muscle for sports and high intensity activities.

My opinion for those who practice Atkins is that while they do lose fat, there is much water loss and most importantly muscle loss. Something we athletes do not want. A CKD is a true fat loss diet that works undeniably, if followed properly and strictly. Yes, low carb diets can be hell at first, but after two to three weeks, there have been anecdotal reports from many dieters that the cravings for carbohydrates decrease. This route to fat burning is unlike any traditional diet all the low-fat diet authors and FDA people have been advocating in history.

I got turned onto this diet a few years back when I got tired of cutting fat and still not being able to lose those last percentage points of bodyfat without losing hard earned muscle. I would start a low-fat diet, and be a either a social misfit (not going out with my friends to party or not going out to eat). Or in the worse case, feel so deprived of delicious junk foods I missed and bail out on the diet all together. One advantage to this diet is that there is no true restrictions on food. One may eat anything labeled a “food”! Well, almost. I’ll explain later.

How the diet works.

The science behind the CKD is simple. Carbohydrates in the diet cause an insulin (a “storage” hormone) output in the pancreas. It is used to store glycogen, amino acids into muscles, while causing excess calories to be stored as fat. So common sense asks me, “How can one try to break down fat, when your body is in a storage-type mode?” Difficult to do, indeed. That is why it makes perfect sense for step one to be cutting carbs.

The next thing that happens in your body is the rise in catecholamines (a “fat mobilizing” hormone), cortisol (a “breakdown” hormone), and growth hormone. Now your body realizes there’s no more carbs to burn for energy, so it must find another energy source: fat.

This usually happens during a metabolic condition called “ketosis.” This is when your liver is out of glycogen and starts to produce ketones (by-products of fatty acids). You can check your status of whether or not you are in ketosis with urinalysis strips you can pick up at any local drug store called “Ketostix.” Just urinate and see if it turns color. If so, you have ketones in the urine.

When the body is fed fat and protein, it will use dietary fat along with bodyfat for energy with protein going towards repair.

As a side note, there is another reason why this diet makes the most sense to use while keeping muscle. When one follows a high carbohydrate, low-fat, reduced-calorie diet, there’s a point when some bodyfat is burned, but when the body is still in a carbohydrate burning metabolism while trying to lose “weight,” it will strip down precious body protein to convert to glucose for energy.

On the other hand, during fat metabolism, protein cannot be converted into free-fatty acids for energy. Although there is no scientific research done on this, there have been reports from followers that there truly is a “protein-sparing” effect. It makes sense doesn’t it? Where else would the body look for fat energy when all dietary fat is burned? Bodyfat.

Diet Requirements Mon. to Fri.

The phrase “working smarter, not harder” applies here more than any diet one has tried. One must fully understand what they must do in order to optimize their goal. To set a CKD up, one cannot just expect to cut all carbs in the diet, train hard, and lose fat! Although some have come up with variations to this plan, the one stated in this article, I have found, has worked for myself (it got me to 6% BF), and other clients I’ve trained to the leanest, hardest they’ve ever been.

First, to set up the diet, write down your lean mass weight. Not your total weight, dough boy. If you weigh 200, but have 20% bodyfat, your lean mass weight would be around 160 pounds. Multiply this by one, getting your grams of protein requirements for a day. Make sure you eat at least one gram of protein/pound of lean mass! This is important in recovery from workouts and enough nitrogen retention to keep muscle. Next, multiply by four, to get your protein calories. Here, it is 640.

The rest of your caloric requirements for the day should be fat. Here is the catch: you must eat fat to burn fat. There’s no way around it. There are many advantages to dietary fat on this diet: Feeling of fullness since fat digestion is slow (less hunger), tastes great, and lowers blood glucose levels (lowering insulin and allow all the fat burning hormones to do their job).

So how much fat? I always recommend starting out with a 500 calorie deficit from your maintenance calories. If you don’t know, it is usually 15 times body weight (full body weight here) depending on an individuals metabolic rate. So here, the example would need 3000 calories a day to maintain weight, and 2500 calories to begin fat loss.

2500 minus 640 (protein calories) is 1860 which works out to be around 206 fat grams a day. Now as you go deeper into the diet, and find the need to restrict calories more, you must cut fat calories, not protein.

The Weekend Carb Load

Since muscle glycogen is the main source of energy for anaerobic exercise such as weight training, we cannot simply deplete all stores while working out and not fill them back up. If that does happen, be rest-assured that the body WILL use protein for fuel then. But this won’t happen on the CKD.

Your one and a half days of “freedom” allow you to do two things: First, reward your carb cravings from the previous days, allowing you to enjoy pleasures like pizza, pasta, breads, etc. Second, eating these things are physiologically rewarding as insulin levels run high, storing amino acids and carbs, as glycogen, into the depleted muscle allowing you to be able to workout again the following week.

Your “carb-up” should begin Friday night and last until around midnight Saturday. Now the next important issue to address is how many carbs. Some lucky individuals find that they eat whatever they want for the 24-30 hour time interval and receive perfect glycogen compensation, while others rely on a better statistical number.

What has been recommended by other authors of the CKD is 10-12 grams of carbs per kilogram of lean mass. Again, time to do math. Our example had 160 pounds of lean mass, so divide that by the conversion factor of 2.2, and we get roughly 73 kg.

100 Grams of easily digested liquid carbs along with around half as many grams of carbs in protein (here 50) as a whey shake or something of that nature should be taken right after the last workout (which I will address in the workout section of the article) when insulin sensitivity will be at its greatest.

A few hours later this individual will start to spread the remaining 630 grams of carbs, along with the important number of 160 grams of protein (remember, keep this constant) during the remainder of the compensation period.

So what about dietary fat? I know you’re reminding yourself, “Didn’t this guy mention pizza?” Yes, I did. And here’s why. During the first 24-30 hours of carbing up, the body will use all dietary carbohydrates to refill glycogen, protein for rebuilding, and get this: fat for energy. Still?

Just like the previous five and a half days. Makes sense. When all the carbohydrates are being used for more important functions (muscle), what else is there to be used? However, you can’t just eat all the fat you want. Keep grams of fat intake below your body weight in kilograms. Again, here our example will keep is fat below 73 during the carb-fest.

By anecdotal reports, this should keep fat regain minimal to nil. Keeping fat intake extremely low has even caused some extra fat burning during the carb up!

As stated before, some dietary fat should be eaten to slow digestion and keep sugar levels stable. Whether it be saturated, unsaturated, or essential fats, is the dieter’s decision. All have nine calories per gram. (Note: there is a claim that essential fatty acids such as flax seed oil increase insulin sensitivity within the muscle cells, in turn, increasing glycogen intake.)

In Case You Missed It

So here’s how it breaks down during the week: Sunday through Friday afternoon , you will follow the low carb diet outlined above. Eat fat and protein all day everyday except on workout days because after workouts, you will need to consume strictly just protein—no fat or carbs.

Some have found to enjoy a protein shake afterwards because they are easily digested. Do whatever works for you. But fat is not logical since you want the protein to fuel the healing process as quickly as possible and fat will only slow it down.

Friday afternoon, around two hours before your last workout of the week, eat two to three pieces of fruit. This will get your body/liver ready to start the carb loading and give you some energy for that final, dreadful workout (trust me, during the first few weeks, you will not want to do that final workout, but you must). Then from Friday night until Saturday at midnight or until bed, eat those carbs!

CKD Workout

Now, the question is, how do we workout to optimize muscle preservation and keep our metabolism up while dieting? Before we get into that, one must realize that during any dieting scheme there is one thing that must be done, and one thing that must not be done.

First, you must keep training volume lower than your usual routine. Overtraining is probably the number one killer in motivation, it deprives sleep, and hinders fat loss.

Second, you must not fall into the myth of lighter weights with higher reps. You got your muscle by benching 240, and you have to bench 240 to keep that same muscle! Or at least around that area! Okay, now that we have that established, here’s what we do:

On Monday and Tuesday we will work our weaker body parts, rest or cardio on Wednesday and Thursday mornings, Thursday do our strongest body parts, and Friday a combination of the Monday/Tuesday workouts in a loop format. The workout I have found to work optimally for myself and my clients is this:

(Note: You may feel free to tweak, shake, and turn this example upside down.

Everybody is different, so find what works for you.)

MONDAY: Chest, Back, Abs

High intensity workouts with 60 sec rest between sets, 90 sec rest between

each exercise

(this excludes all warm up sets)

Bench 3 sets, 6-10 reps

T-bar Row 3 sets, 6-10 reps

Incline bench 3 sets, 6-10 reps

Latpulldown to front 3 sets, 6-10 reps

Dips or Decline bench 3 sets, 6-10 reps

Shrugs 3 sets, 6-10 reps

Flys (any type) 2 sets, 10-12 reps

Reverse flys 2 sets, 10-12 reps

Stiff-leg deadlift 3 sets, 10-12 reps

Rope ab crunch 3 sets, 10-15 reps

Reverse crunch 3 sets, 10-20 reps

TUESDAY: Shoulders, Arms

Same intensity mentioned before

Behind the neck shoulder press 3 sets, 8-10 reps

Military press 3 sets, 8-10 reps

Preacher curls 3 sets, 8-10 reps

French press or “skull-crushers” 3 sets, 8-10 reps

Shoulder raises (any type) 2 sets, 8-10 reps

Hammers 3 sets, 8-10 reps

V-bar tricep press 3 sets, 8-10 reps

Forearm curls 2 sets, 8-10 reps

Reverse forearm curls 2 sets, 8-10 reps

Wednesday: Rest or Cardio

Thursday morning: Rest or Cardio

Later on Thursday: Legs

Same intensity mentioned before

Squat or Leg press 4 sets, 6-10 reps

Lying leg curl 4 sets, 6-10 reps

Standing calf raise 4 sets 6-10 reps

Leg extensions 4 sets, 10-12 reps

Seated leg curl 4 sets, 10-12 reps

Seated calf raise 4 sets, 10-12 reps

Friday night: Final Workout

Same intensity mentioned before

Bench 2 sets, 6-10 reps

T-bar Row 2 sets, 6-10 reps

Incline bench 2 sets, 6-10 reps

Latpulldown to front 2 sets, 6-10 reps

Behind the neck shoulder press 1 set, 8-10 reps

Military press 1 set, 8-10 reps

Either curl exercise 2 sets, 8-10 reps

Either tricep exercise 2 sets, 8-10 reps

Stiffleg deadift 1 set, 8-10 reps

Normal floor ab crunch 2 sets, 10-20 reps

Reverse crunches 2 sets, 10-20 reps

Start the carb up for 24-30 hours!

Aerobics

Before we go on, I want to address the cardio/aerobics issue. Some people find that for the first month on a CKD, cardio/aerobics is not needed. However when fat loss does start to slow down a bit, that is when most start adding 30 min. sessions on their off days. Be careful though, you do not want to hinder your Thursday leg workout. So experiment and try to only add aerobic sessions if you feel you have to.

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