Strength & Conditioning, Types of Muscle Contractions and Exercises
There are many principles related to strength and conditioning. When these principles are applied effectively, then an athlete can maximize his/her athletic potential. The principles can be applied and manipulated to induce a performance outcome. For instance, you can implement certain training procedures to make an athlete faster, jump higher, tackle harder, hit balls farther, and so on.
Strength coaches are the professionals who master this art of manipulating the training principles to maximize an athlete’s performance. It takes an extensive understanding of these principles and the mental, physical, and physiological changes which they produce, to safely and effectively train an athlete. The right strength and conditioning program can make a champion. The wrong program can cause injury or never allow an athlete to reach their full potential.
First you must have a basic understanding of what a repetition is, a set is, what power is, and what strength is. A repetition is one complete movement of an exercise. It usually has two components. The components are a concentric contraction (muscle shortens) and an eccentric contraction (muscle lengthens). A set is a group of repetitions performed continuously without stopping. Power is work (force times distance) divided by time.
So an athlete may run 40 yards (work) in 4.4 seconds. An athlete who runs faster is more powerful. Strength is measured as the maximum amount of force produced. A 400 lbs squat for one repetition (1 repetition maximum) is a measure of strength. Strength is not measured by time. In most sports, athletes will need to be both powerful and strong. Manipulation of training variables will help produce these changes in strength and power.
Types of Muscle Contractions and Exercises
There are various types of muscle contractions and exercises used in athletic movement and all of them may be used at the same time. The following is a list and description of these muscles contractions and exercises.
Concentric Muscle Contractions- When a muscle contracts and shortens it reduces the joint angle. This is a concentric contraction. For example, when you lift a glass of water from the table to your mouth your bicep muscles concentricly contract.
Eccentric Muscle Contraction- When a muscle contracts and lengthens it is an eccentric contraction. Same example, when you lower the glass back to the table it is a eccentric contraction because the bicep is lengthening and controlling the decent of the glass.
Isometric Muscle Contraction- This type of contraction occurs when the joint is in one position and the muscle neither shortens or lengthens. Therefore, no movement results. Same example, if you pick the glass up off the table at a height of 1 inch and hold it at that height, the bicep would not shorten or lengthen.
Isokinetic Exercise- this exercise is done at a controlled velocity at a variable resistance. It must be performed on an isokinetic dynamometer (e.g. Cybex, Biodex, or KinCom). It allows a limb to be isolated and segments stabilized, and it allows the speed (measured as degrees per second) of the movement to be modified throughout the movement.
Isotonic Exercise- this refers to movement of a segment throughout a range of motion. A bench press is an isotonic exercise.
Closed Chain Exercise- it is an exercise in which the end of the chain (link of segments---lower leg, upper leg, and ankle) is fixed to the ground, handle, or wall. A squat is a closed link exercise because the feet are fixed on the floor.
Open Chain Exercises- it is an exercise where the chain is not fixed to the floor, handle, or wall. Knee extensions are open chain exercises.
Principles of Training
Programs should be designed according to the specific injuries sustained, components of movement, and skills required to participate in a particular sport. Each sport will be broken down even further to specific positions, because within each sport are positions that require different skills and different components of movement. Each sport and position will require different energy systems, strengths, endurance, power, and more, all these will have to be trained differently.
Then each individual athlete must be analyzed to determine his/her fitness level. What may be a very hard training program for one athlete may not be a hard training program for another. Therefore one athlete will be maximizing his/her potential and the other will not because the training stimulus will not induce physiological and structural changes.
The next few sections will lay out a general overview of how a program might be designed. Realize that every coach is different and there are many of ways to train for each sport. Successful athletes receive a program that has at least the following components.
Program design should only be done by a strength and condition specialist. If the program is done wrong it will decrease performance and could injure the athlete. Program design is very delicate and only experienced strength and conditioning specialist should implement the training protocols.
The overload principle states that a tissue must be overloaded with a stimulus in order to produce a physiological and structural change. If the stimulus is not enough, then the tissue will have little or no change. If the stimulus is too much, then the tissue may not be able to adapt to the stress placed upon it and it will become injured. The overload principle is a major factor in all training programs. Proper use of this principle will maximize performance and decrease the chance of injury.
Mode of Exercise
Every sport and position is broken down into components (e.g. running, jumping, swinging, hitting, taking hits, etc.). The components that the athlete will need to successfully execute his/her position will depict the mode of exercise used to increase the performance level of the athlete. The mode of exercise is the particular type of exercise used to train an athlete. This may be sprints, squats, jumps, and such. A basketball player may need to execute squats, and various jumping modes of exercise in order to train for the jumping component of his/her sport. Mode of exercise should be sports specific and will greatly depend on or be limited to the training facilities.
Intensity of Exercise
Simply stated, intensity refers to the power output of training. For instance, intensity increases when heavier loads are lifted and/or when movements become faster. The closer the velocity is to maximal, the greater the intensity. Intensity of an exercise can be estimated by a percentage of the 1 repetition maximum (maximum weight an athlete can lift one time). Intensity should be integrated and calculated in every workout session with in a training program.
Assigning the Right Load to Lift
The load is the amount of weight lifted and often goes side by side with intensity. Since intensity is one of the most important aspects of a training program, the load must be chosen carefully for each workout. To little a load per workout and the training stimulus will not be enough to cause an increase in endurance, power, and/or strength. To much load in a workout and the training stimulus may be too much, which will cause injury.
Usually load is chosen as a percentage of the 1RM (maximum amount of weight lifted one time per exercise). Strength coaches know how many reps an athlete can do at certain percentages of their 1RM. For example, if an athlete has a 200 lbs 1RM bench press, and he needs to complete 10 reps, he will have to lift 70% of his 1RM (140 lbs). If he needs to complete 3 reps he will have to lift 90% of his 1RM (180 lbs). The load assignment is important in that the different percentages in weights will hit the energy systems and muscle fiber types harder. This will greatly influence the outcome of performance in an athlete. The strength coach will manipulate the load according to the performance outcome that is desired by the sport and position.
Determining Frequency of Training
The frequency of training refers to the number of training sessions during a period of time. It will be different for each age group and sport. Frequency must be manipulated properly in order to receive the desired gains. Frequency of training depends on the factors listed below.
The type of body movement done during training such as a single joint movement (bicep curl) or a multi joint movement (bench press).
The volume of exercise
The load and/or intensity
The training level or preconditioning level of the athlete.
The goals of training
Whether or not the athlete is injured
Determining the Proper Amount of Rest
The proper amount of rest between sets and between workouts is crucial. To little rest and the athlete may become injured or too much rest and the athlete may not have enough training stimulus. The amount of rest will be determined by the needs in performance. A strength coach will have to balance energy systems, muscle fibers, Wolf’s Law, and more in order to reach the performance needs of the athlete. For example, it only takes about 5-15 seconds to deplete the phosphagen stores of ATP in the muscle at maximum intensities. Yet it takes 2.5-3 minutes to replenish these stores. Therefore, the athlete may need at least 2.5 minutes between sets depending on the training outcome desired.
An athlete will need a proper rest period between workouts as well. In this rest period the body will recuperate and repair. The intensity of training and volume will determine the amount of rest needed. Resting in between workouts, is very important as it gives the athlete the chance to repair tissues and filter out toxins that build up during workouts. Also it allows the athlete the opportunity to replenish their nutritional stores such as carbohydrates and water. Recent studies have shown that well trained athletes can or have the ability to rest less. In other words, they can take shorter rest breaks between sets because their bodies will recuperate faster. In addition, they can achieve a better quality of sleep and rest in between workouts.
Duration of Exercise
Duration is the length of a training session. A cross country runner may run for a duration of one hour (heavy day) three days per week and 30 minutes (light day) two days a week. Duration should be closely monitored because it may cause an athlete to become injured, or it may not induce the desired increase or maintenance of performance. If the same cross country runner ran for 1.5 hours instead of 1 hour on her heavy days, then she may experience stress fractures or other overuse injuries. However, if she only ran for 30 minutes a day, 5 days per week, she may not cause enough stimulus to produce a physiological and structural change.
Sports Specific or Specificity
Sports specific training is training for the components of a particular sport and position within that sport. Each sport has various mental and physical demands. Therefore, athletes must train by imposing the demands of that sport upon themselves. This is referred to as the SAID Principle (Specific Adaptations to Impose Demands). The following is a list of variables that should be considered for the sport in which an athlete is training for, and the program should be designed around the variables.
Speed- What type of speed training does the athlete need to do for his/her sport?
Endurance- What type of endurance will the athlete need for his/her sport (muscular, cardiovascular, or both)?
Muscle Groups- Which muscle groups need to be trained for the athlete’s sport?
Muscle Action- What type of velocity of contraction, synergistic firing of the muscle, and more will be required for the athlete’s sport?
Energy Source- What energy sources will be used, and in what manor will they be used for the athlete’s sport?
Injury Reduction- What type of injuries are suffered in the athlete’s sport and what type of conditioning is required to reduce those injuries (e.g. Football players strengthen neck muscles to prevent neck injuries)
Training volume is used to calculate how much work is being done. Volume is the total amount of weight lifted in a training session. The weight per repetition determines the amount of volume per set of exercise. For instance, one set of the bench press may contain 15 reps at a low weight. A strength coach may calculate it as 2 sets x 20 reps x 100 lbs = 4000 lbs of volume. If they wanted to keep the same volume but increase the intensity they could do 2 sets x 10 reps x 200 lbs = 4000 lbs of volume. Strength coaches will monitor and manipulate volume in order to reach the goals they want throughout their periodization schedule.
The strength coach will look at the season of play. They will plot a map of training according to the fitness level needs during a certain time period of a sport season. A player physically can not keep up maximum conditioning all the time. What he/she will do is peak during the season. This means the athlete will be in his/her best shape, and perform at his/her best. This type of conditioning level cannot be held very long. Therefore, athletes will train for the peak, so that during the season the athletes get in better and better shape, and their performance increases. Athletes want the peak to happen when the competition levels are the highest. This is at the end of the season during play offs, regional, nationals, or world competition.
The goal of periodization is to train year round, so that at that week or two week period of championship type competition, the athlete is not burned out. The athlete will be at his/her best physical shape. There are some coaches who make their bench players run after the game. Parents get mad but they don’t not understand that every game the bench players do nothing physically, while the starters are training (playing) for the entire game. The starters are getting stronger and more physically fit every game, while the bench players are not. Some coaches know this and make the bench players run. Sounds like a horrible thing to do, but if a starter gets injured and a bench player takes over, he/she needs to be in just as good of shape as if he/she had been playing all season.
Periodization can be broken down into phases or mesocycles. Depending on the sport and number of big competitions throughout the year, there may be two or more mesocycles lasting from 1-4 months. The duration of the cycle depends on the goals of the athlete and the time between competitions. Each mesocycle can be further broken down into micro cycles which last 1-4 weeks.
Mesocycle 1 Mesocycle 2 Mesocycle 3 Mesocycle 4
Microcycle 1-4 Microcycle 1-4 Microcycle 1-4 Microcycle 1-4
The first period usually begins after the last game of a season. This is the transition phase. In the transition phase the athlete is allowed to rest and recuperate from the season. The transition phase can last from 1-4 weeks and during this period very little physical activity is done.
After the transition period comes the preparatory period. The preparatory period is usually considered the off season. The preparatory phase will usually begin with high volume low intensity workouts. The athlete will do things like long slow running, low intensity weight room workouts, and low intensity specialty work outs. The activities will progress through micro cycles. The microcycles will slowly intensify while at the same time lower the volume of training. Usually this phase is sub divided into three other phases.
Hypertrophy Phase- this phase is usually done first although it depends on the coach. The phase will concentrate on adding muscle to the athlete. This phase has the largest volume and lowest intensity.
Strength Phase- focuses on adding strength to an athlete. This phase has a moderate volume and intensity.
Power Phase- focuses on adding power to the athlete and contains the lowest volume and highest intensity.
After the preparatory period ends, a small transition periods begins. This period is very short, usually a small 1 week rest period and then 2 weeks of high intensity conditioning (preseason training). Once the transition period is over, the competition period begins.
The competition period will start to slack off of the high intensity conditioning. The athletes will not receive the high intensity conditioning during the competition phase.
Instead the focus is on skills and game strategies. Some people may also refer to the competition phase as the maintenance phase. The athlete will try to maintain everything they gained from the off season training program. The goal of this period is for the athlete to maintain a certain level of performance and to be at the highest level of performance for the most important competitions. The graph below shows that the fitness or performance level of the athlete will rise until the championship part at the end of the season. After the championship period ends, the resting transition period begins.
Each athlete’s progress should be recorded. Some strength programs do this every single workout session so that no time is wasted doing fitness evaluations. It also provides the athlete the advantage of being monitored up to that particular day. Another added advantage is that the athletes will constantly be increasing their training stimulus and that if the training stimulus is too much, it may show in the numbers by a reduction in strength levels. Therefore, the conditioning program can be observed and modified to the optimum level of stimulus.
Otherwise the athlete could end up injuring him/herself because the training stimulus is too much or the athlete may not increase the desired levels of performance because the training stimulus is too weak. This can only be seen when workouts are recorded and calculated everyday, every other day, or every week. Some programs re-evaluate their athletes once every six weeks and then assign new loads to lift. Documenting workouts everyday can be time consuming but it is a very safe and effective way to manage a program.
When an athlete stops training he/she enters a state of detraining. Detraining is a deconditioning process that causes a decrease in physiological capacity and a reduction/change in structural components (e.g. muscle atrophy). Training may be stopped due to an injury or because of periodization. It is important to understand detraining because if athletes detrain to long, they can lose strength, power, endurance, and general athletic ability. Some athletes may decide to taper when they are in-season.
Tapering is a combination of detraining and/or a total reduction in training. It can be an effective way to reduce injuries and increase performance. Detraining can be both the friend and enemy to an athlete. Therefore, it is crucial to understand it, use it, and/or avoid it, depending on the situation at hand.
By: Craig Angle - ME.d, ME.d, ATC, CSCS
Author of the book: How to Raise a Successful Athlete
Former CEO: The Athlete Project
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