A watercraft for transportation and exercise including a boat for floating on water and having a portion thereof above a waterline and a portion thereof below the waterline The boat has an opening therein for permitting a person to be partially below the waterline and partially above the waterline. A sub-frame is operatively attached to the boat, the sub-frame having a lower position at least partially in the water and an upper position at least mostly out of the water. A propulsion device is operatively attached to the sub-frame for propelling the watercraft forwardly in response to movement of the person's feet, the propulsion device having a foot contact portion. The foot contact portion of the propulsion device being disposed a predetermined distance from the waterline in a transportation mode so that that a person can be at least partially above the waterline when using the propulsion device in the transportation mode, said foot contact portion of the propulsion device being disposed in the water and a substantial distance below said predetermined distance when the propulsion device is being used in an exercise mode wherein at such time the person's legs are at least partially disposed below the waterline.