I’m 100% positive he’s wrong…
Firstly, spot reduction is a myth. It does not work like that. You can’t do 100’s of crunches to cut fat from your abs. Your body burns fat from all over. It’s not like by jogging, you’ll only burn fat from your legs. It will burn fat from all over. Having a 6-pack or any muscle tone is a measure of body fat. If you have low body fat, then the muscle’s shape can be seen through your skin. If you have a lot of body fat, then it won’t.
A simple exercise is to take a peice of cloth and wrap it around your hand. You should be able to see the details of your hand through the cloth. Now stick a peice of cotton between your hand and the cloth. The details are now blurred. The more cotton, the less you will see them. In this case, the cloth is is your skin, cotton is fat, and your hand is your muscle.
You have to look at how the muscles energy systems and how the nervous system works.
We’ll use your example of bicep curls. 8 reps… You feel that “burn”? You know what that’s from? That’s from lactic acid build up… You know where the lactic acid comes from? Well, this is how a muscle works. It will first go through it’s ATP stores which is what cells including muscles use for energy. In this case, it’s contracting. Once all that ATP is used up (this happens rather quickly), your muscles need large amounts of ATP to continue contracting. They get them from glycogen (basically sugar) that is stored in the muscle sarcoplasm (kind of a jelly like filler in the muscle). The by-product of converting glycogen to ATP is lactic acid… Feel the burn.
Now if you stress the muscles enough with these types of intense muscular contractions using that amount of energy, they will adapt. They will thing they’ll need more “energy” to meet future demands, so they build more sarcoplasm to store more glycogen to give your muscles more energy. This actually has little effect on your max strength. It will allow you to lift weights longer longer though.
Thus, we just stumbled upon one of the TWO modes of muscular growth (ie hypertrophy) called sarcoplasmic hypertrophy
The actual contractile element of the muscle is in these cords called the myofabrils . They hook together to contract the muscle. They will respond to heavy stimulus as well. The higher the tension, the greater the adaptation. The easiest way to get more tension is to increase the weight. This will cause the myofabrils to respond by growing thicker to handle these heavier loads.
Thus, the second mode of muscular growth is myofabrillar hypertrophy . Since this is a thickening of the contractile proteins themselves, the muscle itself becomes denser of not more noticibly thinker. Think of turning a peice of cork into a peice of lead. Nothing grows, but the lead is obviously denser and stronger.
Now let’s take a look at muscle “tone” again. To be “cut” you will need to have a low body fat. This is done simply by lowering your caloric intake to less than the body actually burns. This will cause a calorie deficit and force your body to go somehwere for it’s energy. That somewhere will be your fat stores, since fat is basically just stored energy to be used in times of need. The easiest way to due is raise your calorie expendture by being more active. Most people do this by running, biking, etc.
Now that your body fat is low, muscles should be visbile. The bigger the muscle, the more visible it is. However, your muscles also need to be dense so the skin doesn’t deform their appearance. Take a look at low weight class power lifters and olympic lifters. They are some dense looking indivuals from all the low rep training they do (ie 1-5 rep range)
Now since you brought up speed, let’s take a look at it. What is speed exactly. What speed is is being able to apply a large amount of force over a very short amount of time. Doing 20 reps of low weight is the exact opposite of speed of training. You are having a very small muscle contraction (ie force) and training it over a long time (20 reps). How on earth will that allow you to have a maximal contraction in a short time? It won’t.
The best way to maximize speed is to initially maximize strength. ie you must maximize how much weight you can lift for 1-3 reps. This is because your are creating a large amount of force in a short time that directly carries over to speed. Eventually you will reach a point where your speed will not be effected by strength gains. When this happens you take 45-60% of your 1 rep max (1RM) and lift it quickly 2-3 times in a row as quickly as possible. This will force your muscles to contract hard and quickly against the weight. Again this is a direct carry over to speed.
Just look at olympic sprinters, football players, etc. The train their speed with heavy weights and fast lifts like speed squats or olympic lifts. They are the fastest people and the highest jumpers in the world. Elite gymnasts are also trained in this fashion once the gymnastics movements themselves fail to effect the athletes’ strength levels.
Anyway, I personally work my 6-pack with heavy weights for strength, explosiveness, and appearance. I do endurance work like you are talking about for endurance… nothing else. Your body adapts very specifically to the demands placed on it. No way will low amounts of force over long periods build your ability to create large amounts of force over a very short window.
He’s wrong. All of whhat I wrote is generally common knowledge in strength training circles. This guy seems like he’s still getting his info from 80’s infomercials.
, there is tons of research that has been done on this subject as well as empirical evidence through experimentation with athletes.