| Rep | A repetition of the exercise you are doing, eg. 5 reps means doing the exercise 5 times in a row without a rest in between. |
| Set | A group of reps followed by a rest. eg 2 groups of 5 reps = 2 sets of 5.
An exercise program will often list exercises to be done a X sets of Y reps |
| Tempo | The speed of the exercise, an exercise done slowly is done at a slow tempo. complex exercise program my split an exercise into a different tempo for different phases of the exercise (eccentric, pause, concentric pause) |
| Concentric | Concentric muscle contractions involve movements that shorten your muscles. |
| Eccentric | Eccentric exercises are exercises that involve lengthening a muscle while still contracting it. |
| Isometric | Exercises are exercises that involve the contraction of muscles without any movement in the surrounding joints. |
| Compound | An exercise that involves two or more simultaneously joint movements. |
| Isolated | An exercise that involves just one discernible joint movement. |
| Closed Chain | An exercise or movement in which the end segment of the exercised limb is fixed, or the end is supporting the weight. Most compound exercises are closed-chain movements. |
| Open Chain | An exercise or movement in which the end segment of the exercised limb is not fixed, or the end is not supporting the weight. Many isolated exercises are open-chain movements. |
| Functional | An exercise which allows one to gain motor development or strength in a manner in which it is used in the execution of a particular task (eg: specific sport skill, occupational task, or daily activity). |
| Hypertrophy | An increase in muscle size |
| DOMS | Delayed Onset Muscle Soreness |
| 1RM | The weight where you can only lift it once for a specific exercise. 3RM and 5RM are also common measures |
| PR / PB | Personal Record / Personal Best |
I will add to this as time permits