First off, there is no such thing as a bad exercise. However, due to the conditions and limitations of a trainee, certain exercises may be contraindicated to the condition of said trainee. For example, spinal issues, the inability to maintain neutral, will render certain exercises such as a squat or deadlift, downright dangerous for that trainee, therefor another exercise would be needed in order to provide safety, in order to improve the FITNESS of said individual. A leg press with a back support would suffice, IF it allows the trainee to move throughout a full or even partial range of motion, safely. Being able to deadlift, squat, or bench press does not determine ones overall fitness, which was my initial point. There are many, many people who cannot execute such movements, yet are incredibly fit individuals. However, there are many who routinely do such movements, while also ignoring aerobic conditioning due to the fear of losing strength, that can’t walk up a flight of stairs without becoming terribly fatigued, not being able to recover. There is no doubt that strength training brings about a faster metabolism, which leads to a fitter and better functioning body. But to suggest that certain exercises are a mandate in order to achieve such a result is completely ignorant, stupid, asinine. If you wanna be better at deadlifting? Deadlift. If you wanna be better at benching? Bench. However, if you wanna get fit? Exercise. The result is to have a better, healthier, and functioning body.