Pedaling for exercise isn't limited to just biking. You can pedal around a lake with your boo in a rented pedal boat. The two of you can work your legs and burn some calories, too. It is a fun workout and being out on the water is sure to have a calming effect on both of you. It's just as easy as pedaling a bike, but you sit side by side so you both have a nice view (unlike a tandem bike).The seating arrangement is more conversational as well. If your workout makes you sweat, you can just jump into a the lake to cool off. You'll still be burning calories and toning your muscles while swimming and treading water. If you live near a lake or are visiting one this Summer, renting a pedal boat is fairly inexpensive (less than $40 for three hours), but it's totally worth it. Just make sure you have enough energy to pedal back to shore!