Fast Twitch Vs. Slow Twitch Muscles

There are two main classifications of muscle fibers: Slow-Twitch muscle fibers (Type I) and fast-twitch muscle fibers (Type II). There is a lot of debate regarding the body’s ability to adapt its muscle fibers from one type to another. Some studies seem to show some ability to affect muscle fiber type with training, while other studies show no correlation.

Type I fibers are able to use oxygen more efficiently. Slow-Twitch muscles, as the name suggests, fire more slowly than fast-twitch muscles. These fibers are most efficient when performing high rep low weight actions. This becomes important in anaerobic exercise such as running a marathon. It is found that marathon runners tend to have higher percentages of Type I fibers, though the cause-effect relationship is not known. It could be that marathon runners have a high percentage of Type I fibers due to the training, or it could be that people with low percentages of Type I fibers simply do not become marathon runners.

Type II muscle fibers are further categorized into Type IIa and Type IIb fibers. Type IIa fibers can be thought of as hybrids between slow twitch and fast twitch muscles. These muscle fibers can alternate efficiently between anaerobic activity and aerobic activity; this essentially gives you the best of both worlds, as far as performance is concerned. Type IIb muscle fibers are the iconic fast-twitch muscles. These fibers allow your body to perform high velocity high power movements, such as jumping high, or bench pressing high weight at low reps. The limitations of Type IIb fibers come from the recovery time. Since these fibers perform best during aerobic activity, these muscle fibers tend to fatigue more easily and tend to take longer to recover than Type I or Type IIa. This effect can be mitigated by making the body more efficient at delivering oxygen to these muscles, so that these fibers do not become oxygen deprived quickly.

Each play an important role in your body, and no person has all of one type or the other. Regardless of your body’s ability to change the muscle fiber types, training in a desired type of performance will always show improvement over time.

Is Spot Reducing Possible?

Many people are under the impression that they can simply lose stored body fat in a particular area of your body by doing the associated exercise for that area. For example, if someone wants to lose stomach fat, you may find them doing a lot of crunches. I have also witnessed those who are under the impression that arm fat can be lost by doing arm workouts. While toning those areas can make the fat seem less apparent, you will not necessarily lose fat just by doing the targeted exercises. It is simply not possible to target a specific area of fat on your body. You can do as many crunches as you’d like and the stomach fat won’t budge.

 Overall Body Fat

Losing fat in a particular part of our body will also require you to lose fat everywhere else. This is done simply by burning more calories than you eat.

Eating at a calorie deficit and exercising to burn calories is a great way to lose body fat. This will require that you carefully dial in the amount of calories you need to eat each day to lose fat.

 The First Step

The first thing you need to do is determine what your maintenance calorie level is. This is called your Basal Metabolic Rate (BMR). Your BMR is calculated by your height, weight,age, and gender. The resulting number is about the amount of calories your body would burn if you were to sleep all day. Once you know your BMR, you just need to use the Harris Benedict Formula. This will factor in your activity level to find out your daily caloric needs in order to maintain your current weight.  Eating below this number will result in weight loss.

 Note: it’s recommended that you start eating at only a daily calorie deficit of 100-200 calories. Monitor your results closely and adjust your calorie intake accordingly.

Once you figure out you daily calorie intake requirements, you can begin putting together a nutrition plan.

You should eat an adequate amount of protein so you can retain muscle mass while losing fat.

Your stubborn fat areas will begin to improve overtime if you can stay consistent in your weight loss plan.

Understanding Meal Frequency – I Know How Much to Eat, But When?

Should I eat more calories in fewer meals, or less calories more often? Should I skip breakfast, dinner? If I eat a snack, do I have to wait 30 minutes before I go swimming? If you ask a dozen different people about how frequently you should eat throughout the day, you will likely get at least a dozen different answers. A lot of weight (pun intended) is put into choosing how often to eat, and how much to eat at each meal. People often spend as much time planning the timing of their meals as they do the workout itself. But to answer these questions, we need to go back to our roots. Our bodies are designed to use food to expend energy, repair itself, and to adapt to the environment. And back in the day, when food required a little hunting and gathering, this meant eating whenever you were hungry. The scarcity of food, and the need to expend energy to obtain it, not to mention survive, justified eating whenever possible, and kept our ancestors from becoming slobs. Nowadays though, when 2,000 calories are obtainable in a meal ordered from the comfort of your favorite air conditioned vehicle, a little more restraint is necessary to limit the body’s resources relative to your personal energy expenditures.

Note that I said relative to YOUR body’s energy expenditures. Now I know a lot of people who want to have a body like Michael Phelps, and I would like to help them do that. But I am not going to run around telling people they should eat 12,000 calories per day (the calorie intake of Michael Phelps) which, if you have ever tried to eat that much, you might know requires eating huge meals constantly throughout the day. I wouldn’t give that advice unless… this particular individual finds themself training 8 hours per day in a swimming pool (and I mean more than just water aerobics) and hitting the gym in their free time.

So here is the question, should Michael Phelps be worried about spacing his meals, or skipping breakfast? The answer is plainly no. His body needs a certain amount of macro-nutrients (proteins, carbs, etc.) to sustain his activities. As long as he is getting all the nutrition he needs, he will be getting the most out of his workouts, repairing the strain on his body, and adapting to new techniques and demands that are put on his body. If he were to not get enough nutrients, he would have to worry about catabolic processes, and if he were to double his calorie intake, yes even Michael Phelps could get fat.

I know many of you are thinking that a comparison with an Olympic athlete is too extreme. You think that perhaps he has a genetic predisposition to shedding body fat. Questions about genetic predisposition and personal dietary specialists begin bubbling to the surface, but the reality of the situation is that you could take almost any competitive athlete and you will find the same results. Think of the offense of a football team, and compare a wide receiver to a lineman. Either one of them is expending more energy than you or I on a daily basis, but a wide receiver stays slim and a lineman stays hefty. Look at a picture of Dan Marino now without a shirt and compare it to him years ago. It is not the result of them spacing their meals with regard some arbitrary concept of time invented by humans much later than we began existing. It is a result of eating a quantity of food relative to the activity level of the individual.

If you need to eat smaller meals more frequently to be able to get all your protein, or to help avoid unhealthy snacking throughout the day, or if you need to eat larger meals less frequently to feel satisfied, then go for it. Don’t under-nourish your body, and remember to balance the amount of food you eat with your activity level. Take control of your body.