Final answer:
A rest period of 48 to 72 hours is generally recommended before training the same muscle groups in high intensity/vigorous strength training, allowing muscles to recover, prevent injuries, and ensure muscle growth.
Step-by-step explanation:
Regarding high intensity/vigorous strength training, rest is crucial for muscle recovery and growth. After subjecting muscles to the stress of weightlifting, they need time to repair and adapt to handle heavier loads, which is essential for increasing muscle size. The recommended rest period before targeting the same muscle groups again is generally 48 to 72 hours. This rest period helps prevent overuse injuries, promotes the healing of the sarcolemma and myofibrils within muscle fibers, and allows for the incorporation of new structural proteins, leading to increased muscle mass. Ignoring adequate rest can lead to tendon damage, skeletal damage, and diminished performance. Remember, increasing the intensity of exercises over time by lifting heavier weights is necessary to continually challenge your muscles and produce gains in muscle mass.