Final answer:
The minimum recommended time to hold a static stretch for effectiveness is 20 seconds, as this allows muscles to relax and lengthen.
Step-by-step explanation:
The minimum recommended time to hold a static stretch is 20 seconds. This duration allows the muscle to relax and lengthen, which can help in improving flexibility and range of motion. Holding a stretch for less than 20 seconds may not provide the same benefits, while longer durations can increase flexibility further, but the minimum effective dose is typically around 20 seconds for most individuals.