Definition of Terms

Strength trainingThe use of resistance methods to increase one's ability to exert or resist force. The training may include use of free weights, the individual's own body weight, machines, and/or other resistance devices to attain this goal.
Core strengtheningFocusing a strengthening program to the muscles that stabilize the trunk of the body. The training emphasizes strengthening of the abdominal, low back, and gluteal muscles as well as flexibility of muscular attachments to the pelvis, such as the quadriceps and hamstring muscles.
SetA group of repetitions separated by scheduled rest periods (eg, 3 sets of 20 reps).
RepsAbbreviation for repetitions.
One-rep max (1RM)The maximum amount of weight that can be displaced in a single repetition.
Concentric contractionThe muscle shortens during contraction (eg, arm curl, leg press).
Eccentric contractionThe muscle lengthens during contraction (eg, lowering a weight).
Isometric contractionThe muscle length is unchanged during contraction (eg, wall sits: athlete holds the position of feet planted flat on ground with knees at a 90° angle and back against the wall).
Isokinetic contractionThe speed of muscle contraction is fixed through the range of motion.
Progressive resistive exercisesAn exercise regimen in which the athlete progressively increases the amount of weight lifted and/or the number of repetitions. The more repetitions, the greater the work performed and the greater the endurance development. The more weight lifted, the greater the strength development.
Plyometric exercisesRepeated eccentric and concentric muscle contractions, such as jumping up onto and down from a platform.
WeightliftingA competitive sport that involves maximum lifting ability. Weightlifting (which is sometimes called Olympic lifting) includes the "snatch" and the "clean and jerk."
Power liftingA competitive sport that also involves maximum lifting ability. Power lifting includes the "dead lift," the "squat," and the "bench press."
Body buildingA competition in which muscle size, symmetry, and definition are judged.