You are an endurance athlete when you start training for long-distance running events from 3k to more than a marathon; when you train for 40k cycling time trials to the over 100k gran fondo; when you train for a sprint triathlon to the famous Ironman.
Whatever you do, you spend long hours training for your sporting endeavours. As a triathlete, you spend hours swimming, biking and running every week. You do your quality interval training workouts. You even spend time doing your mobility (flexibility) and stability work where you do your foam rolling, strength (and core strength) and dynamic stretching routine and make sure that you are trying to remain a balanced athlete. You do what you need to do to stay injury free, to remain symmetrical functionally.
The question you should ask yourself is: Is there more you can do? The answer is yes, there is more you can do if you are functionally balanced, symmetrical and mobile. Power and plyometrics come to mind. The idea here is to become an overall rounder athlete. If you were a soccer player, where you usually work on speed and power, to become a more round athlete, you would have to include some endurance related exercise routines; if you are an endurance athlete, you will want to include some power/plyometric into your routine.
The goal of doing plyometrics is to apply optimal force (strength) and speed in the right direction and efficiently. This means that while you are working on plyometrics, explosive strength improves (useful when sprinting at the end of a race), reactive strength improves (useful on a getaway) and you become more efficient at transferring force (less waste of energy so, also useful when racing).
Plyometrics training is also a great way to help prevent injury. When doing explosive type of training, your body becomes more tolerant to stretch loads at various speeds (Stretch Shortening Cycle). In addition, your body increases its readiness to react to any change of direction and situation that would otherwise over lengthen the muscle when landing and decelerating, whatever your sport. Your ability to respond to any situations improves because your body becomes more resilient to change. In short, not only do plyometric exercises improve performance factors, they also decrease biomechanical risk factors that could be related to tissue tears.
The cool thing about it is that you do not need to do a huge amount of volume to become effective. You can include plyometrics exercises in your movement preparation routine in order to activate key movement patterns or to get ready to go fast in your sport. It is important to avoid fatigue during that time. What you are looking for is activation, which means, no more than 6 repetitions per movement specific to your sport and no more than 2-3 movements (5-15 minutes max).
One movement I enjoy doing myself is the continuous lateral horizontal 45 degrees bound. Before attacking plyometrics, you need to sort out any functional issues related to your level of activity. If you have done a functional movement screen, it is not advised for you to work on strength and plyometrics if you do not pass. You want to avoid compensations. If you strengthen dysfunctional patterns, you will remain dysfunctional and inefficient. Slow and right beats fast and wrong but once you are slow and right, it is important to progress to fast and right ;).
Good luck on your training and try something new!