Stretching of human skeletal muscles is defined as a series of manipulations of joint positions aiming to increase muscle-tendon and tissue extensibility and maximal joint range of motion (flexibility). Stretching is also used for recovery after intense exercise to induce muscle relaxation, to reduce pain and muscle soreness. Furthermore, there is evidence suggesting that stretching may reduce the risk of musculotendinous injury and contribute to rehabilitation following injury or disease. Static and dynamic stretching are commonly used in the warm-up to prepare the muscle-tendon unit for performance, while static stretching and proprioceptive neuromuscular facilitation (PNF) stretching techniques are employed usually during recovery and rehabilitation. Recent research suggests that long-term stretching training can induce muscle and connective tissue regeneration, such as sarcomerogenesis and fascia remodeling, as well as changes in muscle morphology and architecture (i.e., increases in muscle fascicle length and angle, muscle thickness and cross-sectional area) associated with improved muscle contractile function. The beneficial effects of stretching training before and after exercise, as well as its long-term adaptations should be adopted by practitioners who wish to enhance performance and accelerate recovery in sport and exercise.