Exercise is important. Not many people would dispute that idea, including even the most sedentary couch potatoes.

Working out is good for your body and mind. It can boost energy, improve your muscle strength, and increase endurance. Physical exercise raises the heart rate, which in turn pumps more oxygen to the brain. It also improves your mood by increasing the amount of serotonin, a neurotransmitter that is associated with good health and mental well-being.

Even so, most people don't get enough exercise,  and they know it. They are less sure, however, how often and how much exercise they should be doing.

To get answers to such questions, Micheal de Medeiros of Popsugar spoke with Philip Cruz, a certified Strength and Conditioning Specialist and Youfit Health Clubs' Master Trainer.

Image courtesy of: libbywithnall

The first issue they addressed was how many days a week you should exercise.

Cruz recommends you aim for at least three workouts a week on nonconsecutive days.

“If you choose to work out more often, plan on changing up the intensity of the workouts so that your body can recover after a tough workout,” he told POPSUGAR. That means if you just tackled a day full of lower-body exercises, like squats, lunges, and deadlifts, you'll want to balance out that workout with a lower intensity cardio session to help with recovery.

Cruz also cautioned that, if you do work out on back-to-back days, you shouldn't train the same muscle group intensely, so your body can recover and come back stronger.

The second question addressed was how long should you exercise.

Cruz recommends that “workouts last anywhere from 30 to 90 minutes.” The range depends on the intensity of the workout. The rule of thumb is, the more intense the workout, the shorter it should be.

For longer workouts Cruz suggests splitting them up into 30 to 45 minutes of weight training, then finishing off with 20 to 30 minutes of cardio. If you're a bit squeezed for time, Cruz's go-to workout is a 30-minute circuit or high intensity workout.

Finally, the two addressed what exercise is best.

“There are many different ways of working out,” Cruz told POPSUGAR. “You can do an interval style workout on the elliptical, resistance train using cables or free weights, or even take a group class.”

Variety and consistency are the key. By continuing to do similar workouts and exercises over time you'll feel the movements get easier, and you'll get that satisfying feeling of moving up to the next pair of dumbbells. If you're sticking with three days per week, Cruz recommends breaking those days up into upper body, lower body, then finishing with a core and cardio workout.

To read the entire article, go to Popsugar's page.