A Aerobic Fitness - Aerobic training is any sustained activity that increases your heart rate for 20 minutes or longer.   B Balance - Developing a balance between muscle groups. > more   Breath Control - As a general rule, one should exhale during the positive (concentric) phase of contraction as the weight or weight stack moves away from the floor, and inhale during the negative (eccentric) phase as the weight returns toward the floor.   C Concentric Contraction or "positive" phase - For example, on the upward phase of the biceps curl, the biceps are shortening. This is a concentric (positive) contraction. During the lowering phase of the curl, the biceps are lengthening. This is an eccentric (negative) contraction.   D     E Eccentric Contraction or "negative" phase - For example, on the upward phase of the biceps curl, the biceps are shortening. This is a concentric (positive) contraction. During the lowering phase of the curl the biceps are lengthening. This is an eccentric (negative) contraction.   F Full Range of Motion - To obtain optimal gains, the overload must be applied to a joint and its associated muscle, through its complete range starting from the pre-stretched position (stretched past the relaxed position) and ending in a fully contracted position. This is crucial to strength development.   G     H     I Isometric Contraction produces contraction but no movement, as when pushing against a wall. Force is produced with no change in the angle of the joint.   Isotonic Contraction causes a joint to move through a range of motion against a constant resistance. Common examples are push-ups, sit-ups and the lifting of weights.   J     K     L     M Max -This is a repetition performed against the greatest possible resistance (the maximum weight a person can lift one time). A 10-RM is the maximum weight one can lift correctly 10 times.   Muscle Failure is the inability of a person to do another correct repetition in a set.   Muscular Endurance is the ability of a muscle or muscle group to do repeated contractions against a less-than-maximum resistance for a given time.   Muscular Strength is the greatest amount of force a muscle or muscle group can exert in a single effort.       N Negative or Eccentric Contraction - For example, on the upward phase of the biceps curl, the biceps are shortening. This is a concentric (positive) contraction. During the lowering phase of the curl the biceps are lengthening. This is an eccentric (negative) contraction.   O One-repetition maximum (1-RM), also referred to one's maximum or max is a repetition performed against the greatest possible resistance (the maximum weight a person can lift one time). A 10-RM is the maximum weight one can lift correctly 10 times.   Overload - For a muscle to increase in strength, the workload to which it is subjected during exercise must be increased beyond what it normally experiences. In other words, the muscle must be overloaded. Muscles adapt to increased workloads by becoming larger and stronger and by developing greater endurance.   P Positive or Concentric Contraction - For example, on the upward phase of the biceps curl, the biceps are shortening. This is a concentric (positive) contraction. During the lowering phase of the curl the biceps are lengthening. This is an eccentric (negative) contraction.   Q     R Recovery - Allowing your body to rest and rebuild.   Regularity - Exercise must be done regularly to produce a training effect.   Repetition - When an exercise has progressed through one complete range of motion and back to the beginning, one repetition has been completed.   S Set - This is a series of repetitions done without rest.   T     U     V Variety - Using different equipment, changing the exercises, and altering the volume and intensity of exercises is a good way to add variety and produce better results.   W     X     Y     Z