If your cat eats dry food, he's more prone to constipation than a cat who eats wet food due to the decreased moisture content. Your vet will do a simple test to determine your cat's hydration level by pinching a fold of skin on his shoulders and pulling up. If it snaps back into place when released, he's well hydrated.
Comparing the Calorie Burn. In terms of calories, a 30 minute treadmill running session at 6mph for an 155lb adult will burn around 350 calories. The same size adult will burn around 260 calories in 30 minutes on a Spin bike at a steady pace. However, a Spinning class is much more intense so you can expect to burn anywhere from 400-600 calories if you push yourself.
Consider Your Weight and Pace. Your weight and pace dictate how many calories you can expect to burn on an exercise bike. According to HealthStatus, a 145-pound person burns around 231 calories in 30 minutes of pedaling moderately and around 374 calories in 30 minutes of pedaling vigorously. During the two workout tempos, a 195-pound person burns about 310 and 503 calories, respectively.