Q: First of all, I was wondering if you could explain what role hormones and the endocrine system play in strength and power production. For instance, I have read that testosterone levels influence strength and power, but I wanted to know exactly how it does this. I know that it can affect strength and power indirectly through its impact on muscle size and bodyfat, but does it have any direct effects? Does increased testosterone have a stimulating effect on the nervous system that allows for more muscle fiber recruitment? If so, is this another reason why kids get stronger when going through puberty in addition to the muscle size increase?

Also, I am curious to know exactly why it is that when one performs or mimicks a specific skill with added resistance such as swinging a baseball bat with a doughnut in the on deck circle or doing vertical jumps from a standstill position while holding dumbbells that they are able to move faster and with more force in the same movement immediately afterwards when the resistance is removed. Does this really make you perform more powerfully than you would under normal circumstances or is it just some kind of kinesthetic illusion that makes you feel as if you are moving faster. If it does in fact make you temporarily more powerful, is this because it tricks the body into recruiting more motor units than it normally would since it thinks it is still dealing with the heavier resistance?

A: For the first part of your question science still doesn't have all the answers, but yes, testosterone directly influences virtually every organ and system in the body. There are actually more testosterone receptors in the hypothalamus then there are in the muscle. Training while natural and training while assisted would be like running a stock race car on regular gas up against a full bored modified race car on nitrous oxide. The body simply does everything better and everything is enhanced. If anything I'd say the effects of steroids on athletes in general are vastly under-rated not over-rated.

As for your 2nd question, the after-effect phenomenon,- any stimulus on the body leaves traces which linger for a period of time after. This is why if you stand in the middle of a door frame, push out with each arm for 45 seconds, and then step forward while relaxing your arms, your arms will "float" up in the air seemingly on their own. Research is inconclusive as to whether or not this is of any value when considering speed-strength activities (swinging bats or throwing shotputs etc.) There is evidence that what's mainly experienced in these situations is an illusion that you are moving faster or easier. However, the research is clear that dynamic activity is enhanced by subsequent heavier activity providing the resistance in the dynamic activity is 50% or more of maximum. Thus, if you hold a very heavy weight and follow this up by lifting a pretty heavy weight you can expect to lift more weight then you would otherwise. However, if you swing a loaded bat and then swing a regular bat you might "feel" like you're moving faster but may not actually be.

Q: My 16 year old son has tried a lot of different programs, jump shoes,ect. The only program that he has been through that has helped is a Frappier Acceleration program. Are you familiar with the Frappier program? One thing they do at Frappier that I think would be hard to match would be their speed training with the super treadmill. Is there something to be said about forced speed training and muscle memory? After reading your book and testing my son we have figured out that his limit strength is deficient. My son just started one of you strength programs and when he gets done he would like to go through the frappier program again. The only thing that I can see he possible could gain from is the speed training on the super treadmill. I know you have speed programs in your book but how does it compare to a frappier program? I know you went from running a 5.0 to 4.27 without the help of a super treadmill. I also know that a lot of pro athletes are using the frappier program in the off season. I guess I don't know for sure what to tell my son when he wants to go through the frappier program again. One thing I do know for sure is the difference in the price of your program vs. Frappier $300.00. Any advice you can give me would be appreciated.

A: I think this is a case of "anything" being better then "nothing". There is nothing miraculous about the frappier treadmills...if you were to take young kids out on a field and have them do the same type of training on grass..simply running sprints with a coach a few times a week they would improve just as much if not more...but simply the fact that they have an organized format to follow and someone pushing them allows them to get results.

I've taken a look at the frappier system and it's been come down on pretty hard by various sprint coaches around the country. The argument is that treadmills were originally used on horses during winter to allow them to run when there was snow and ice on the ground. When they went back to the regular surface they were always slower not faster. The ground contact times are different because the treadmill moves vs the athlete moving. In sports, top speed is of little significance rather it's the rate at which you can accelerate to top speed that is important. Those at frappier seem to focus to much on top speed running and top speed mechanics. There are also no top sprint athletes who train on the treadmills for anything other then conditioning. I also have a problem with the strength program that they employ using all machines with too much quadricep empahsis and not enough emphasis on the posterior chain.

As for forced speed training and muscle memory, the rate at which the legs cycle is not a limiting factor in sprinting. The limitation is the ground reaction forces exerted with each footstride and the ability to overcome the bodyweight. One can lie on their back and cycle their legs much faster then they can during an all out sprint. By the "overspeed muscle memory" logic, this would be an excellent speed exercise since the limbs are cycling at a greater rate then in a sprint. But in the real world we know different. In addition, overspeed training changes up the mechanics of the sprinter, causing a braking effect that not only detracts from solid technique but can also lead to injury.

Truthfully, frappier programs are popular because the general public will spend more money on fancy gimmicks becuase they think something is cutting edge then they will on hard work. In addition, space is expensive nowadays and most trainers and gyms don't have the room or the money to put up a track or a field to have their clientele run on. You can't even go out and run on an empty field without someone trying to sue you. Why should you spend the money to put up a track when you can just buy a treadmill and make more money anyway when you advertise it as cutting edge? In addition, it's a lot easier to hang out in an air conditioned room and run athletes on a treadmill one by one then it is to go outside in the hot sun and battle the elements.

Having said all that, for $300 I wouldn't hesitate to encourage my 11 yr old nephew to enroll in a frappier program if that's all he had available simply because I know, although it may not be "perfect" and may not be as good as what I can do taking him out on the field and in the weight room.....I know that if it's being paid for that his parents will make sure he shows up 3 times each week (or however often)...and I know that there are gonna be other kids around there that he's gonna look forward to competing against and he'll like that.......and I know that he probably thinks it's a lot more cutting edge and effective then the "Rocky" type workouts I'd have him doing. All those things combined are worth something.

So I'd say if he enjoys it then let him do it. It's not perfect but I'm sure he'll get results as long as he does something.

-kelly

Q: Do you think that some people are able to jump higher with more muscular weight and strength then others? I've been thinking that perhaps some people's CNS won't allow them to "easily" express more power at a higher weight even if they have more strength and hypertrophy and are lean.

Yes I think you're right but a lot of it depends on muscle distribution. Where is that weight going? Most of the extensors, the quads, calves, shoulers, and triceps are in my opinion "slow man's" muscle groups. Those are the groups that become developed to a great extent on typical bodybuilders and can contribute to excess dead weight. In contrast, the traps, erectors, lats, biceps, hamstring, and glutes are "fast mans" muscle groups. They are high density fast twitch muscles that contribute to high speed force production. You won't find many good explosive leapers who don't have thick erectors, good lat development and good posterior chain development. The extensors hypertrophy at a greater extent then the flexors in most people, yet if you take a look at the good athletes you will see the exact opposite, the flexors hypertrophy moreso then the extensors and they are blessed in the flexor department with lots of natural muscle cells.

Most individuals do not naturally have the correct muscular structure so they should train for it in my opinion. Before you can flye right you must look right. That means most people need glute development with lowered bodyfat before they can ever think about being explosive. Squats and a proper diet will go a long way.