Chapter Outline

FLEXIBILITY

As we age, flexibility tends to decrease. Disuse, injury, excessive body fat, and muscle imbalances contribute to this loss of range of motion.

Flexibility can be maintained by incorporating regular stretching into workouts.

BENEFITS AND CAUTIONS

Flexibility benefits include: decrease in risk of injury; counteract of age-related declines in flexibility; decrease in aches and pains; increase in the ability to move freely; enhancement of athletic performance; and it reduces tension.

Cautions include: overstretching of cold or tight muscles; competitive stretching; and stretching injured muscles and joints.

TYPES OF FLEXIBILITY

Static flexibility refers to the range of motion achieved through slow, controlled

stretching.

Dynamic flexibility refers to the range of motion achieved by quickly moving a limb to its limits.

PRINCIPLES OF FLEXIBILITY DEVELOPMENT

Flexibility is specific to each joint, is partially genetically determined, and is determined by joint structure, elasticity of muscle, and connective tissue.

Flexibility gains are proportional to the overload applied.

GUIDELINES FOR FLEXIBILITY DEVELOPMENT

Guidelines for stretching, to name a few, include: warm up first; stretch muscle groups to be used in the workout; stretch during the cool-down for flexibility gains; hold, don't bounce.

FLEXIBILITY EXERCISES FOR BASIC FITNESS

There are nine key stretches for basic fitness.

PNF PARTNER-ASSISTED STRETCHES

PNF stretches are very effective for increasing flexibility.

Hold the static stretch; then contractthe muscle to produce fatigue; then relax while a partner stretches the limb.

MUSCULAR FITNESS

Muscular fitness programs enhanceone's appearance, increase muscle mass, shape and tone muscles, and increase muscular strength and endurance.

RESISTANCE TRAINING: BENEFITS AND CAUTIONS

Resistance training can help with weight control, weight gain, appearance, time economy, energy levels, athletic performance, injury prevention, bone strength, flexibility, balance, and more.

MUSCLE FUNCTION

Muscles are made up of individual muscle fibers bound together and sheathed in

connective tissue. There are two types of muscle fibers: slow-twitch and fast-twitch.

Slow-twitch muscle fibers have good endurance but low power. Fast-twitch muscle fibers are able to contract quicker and stronger, and increase in size better in response to training.

Muscle fibers are genetically determined, and one cannot change into another.

The contracting muscle is called the agonist; the opposing muscle is the antagonist.

DETERMINANTS OF MUSCULAR FITNESS GAINS

The types, number, and size of muscle fibers one possesses, as well as how efficiently the muscular system recruits them, determine muscle fitness development.

Types and number of muscle fibers are genetically determined; size and muscle fiber recruitment are a product of training.

MUSCLE FIBER RECRUITMENT

When a muscle contracts, only the number of muscle fibers required for that momentary effort will shorten.

To develop maximal strength, try to recruit as many muscle fibers as possible by working the muscle to a state of temporary muscular failure.

MUSCLE ATROPHY AND HYPERTROPHY

Since muscles adapt to the load placed upon them, if they are not used, they grow weak, stiff, and shrink in size (atrophy).

When muscles are stimulated by an increased workload, the increase in size (hypertrophy).

TYPES OF STRENGTH TRAINING PROGRAMS

The three types of muscle contractions are isometric, isotonic, and isokinetic.

ISOMETRIC

The muscle contracts, but does not change in length, and no movement occurs. (Example = pressing palms together.)

ISOTONIC

As the muscle contracts, tension is controlled throughout the motion. Isotonic contractions are either concentric or eccentric.

In a concentric contraction, the muscle shortens as it overcomes resistance. (Example = the biceps muscle contracts during a biceps curl.)

In an eccentric contraction, the muscle lengthens and contracts at the same time. (Example = the biceps muscle contracts eccentrically during the lowering phase of a bicep curl.)Eccentric contraction is a vital component of strength development because it makes up half of the effort.

Strength increases can occur with eccentric lifting alone because you can lower more weight than you can lift.

ISOKINETIC

The resistance is adjusted to maintain a constant rate of contraction. The load is controlled bythe efforts of the user. (Example = Cybex machines or sweeping an arm through the water - the harder you press, the more resistance you create.)

PRINCIPLES OF RESISTANCE TRAINING

Principles of resistance training include progressive overload, specificity, and recovery.

GUIDELINES FOR DEVELOPING MUSCULAR FITNESS

In increasing muscular strength, endurance, or power, the key variables are resistance, repetitions, and speed.

To develop strength, exercise at 80 to 95 percent effort for a few (4-6) repetitions.

To develop endurance, exercise at 50 to 60 percent for many (15-20) repetitions.

For general conditioning, exercise at 70 to 75 percent for 8-12 repetitions.

Development of muscular strength also produces some increase in muscular endurance; however, muscular endurance does not enhance strength.

Muscular power, a function of strength and speed, is the ability to apply force rapidly.

The guidelines for obtaining optimal results from a resistance program include: sequencing from large muscle groups to small muscle groups; using correct form; resting between sets; maintaining balance of opposition muscles; breathing correctly; and moving in a smooth, controlled manner (2 seconds to lift, 4 seconds to lower).

RESISTANCE TRAINING PROGRAMS

There are many types of resistance-training programs. The program selected depends on personal goals and types of equipment available.

WEIGHT TRAINING

Weight training is a noncompetitive method for anyone to build muscular fitness.

Using either free weights or machines, there are a variety of exercises that can strengthen and tone a variety of body parts.

HOW TO BEGIN AND PROGRESS

For general conditioning, do 1-2 sets of 8-12 repetitions 2-3 times per week. Increase

the workload when 12 reps can be easily done.

Depending on one's goals, changing the workload, recovery period, number of sets, or reps is a way to incorporate variety in the workout. It is best to change only one variable at a time.

Using proper form, breathing, and progressions will help eliminate discomforts and the possibility of injuries.

HOW TO SHAPE AND TONE WITHOUT WEIGHTS

Many exercises can be done at home or while traveling that shape and tone muscles without the use of special equipment.

Abdominal crunches, side-lying leg lifts, and push-ups are just a few examples.

Elastic resistance bands or tubes can be used to strengthen and tone a variety of muscle groups.

Partner resistance exercises allow you to work with a partner who adds resistance to various exercises.