Final answer:
A long interval(TR1) workout involves short bursts of high-intensity exercise followed by longer periods of medium to varied muscular work. Hence the correct answer is option A
Step-by-step explanation:
A long interval(TR1) workout is a pattern of physical exercise that involves short bursts of high-intensity exercise followed by longer periods of medium to varied muscular work. This type of workout is characterized by alternating between intense exercise and rest periods.
Hence the correct answer is option A