be full of piss and vinegar

To have an abundance or excessive amount of boisterous, youthful energy, enthusiasm, or rowdiness. Although we were full of piss and vinegar, our team just didn't have the skill necessary to beat our cross-town rivals. It took having kids of my own to remember how a child can be full of piss and vinegar at 6 AM. My college intern is always full of piss and vinegar, whereas I don't have any energy at all until my third cup of coffee.