If Carter Mario was having second thoughts about competing in an intense, indoor rowing competition, maybe the so-called “vomit buckets” should have stopped him dead in his tracks.

The basins next to the rowing machines at the international event at Boston University last February are as much a testament to the physical demands of the event as are the muscled bodies willing their way toward a virtual finish line. But Mario, a personal injury lawyer in Milford, is used to challenges.