Protein should provide about 15% of a healthy person's daily calories. As a rule of thumb, people of both sexes and any size will do fine with about 60 grams of protein a day. Athletes who have large muscles and work out hard may need 20% more. But even that's not very much; 8 ounces of chicken or 6 ounces of canned tuna, for example, will fit the bill.
It's easy to get lost in a killer playlist or Friends rerun on the TV attached to the elliptical, but mindless exercise makes all your hard work forgettable—and you can forget about seeing results too. “There is a huge difference between going through the motions of an exercise and truly thinking, feeling, and engaging the key muscles,” says Kira Stokes, master instructor at the New York City location of indoor cycling studio Revolve. “Be conscious of and enjoy the sensation of your muscles contracting and the feelings of growing stronger and more powerful with each rep.”
If motivation is your hang-up, change your exercise routine every 14 days. A University of Florida study discovered that people who modified their workouts twice a month were more likely than to stick to their plans compared to those who changed their regimens whenever they wanted to. Boredom didn’t appear to be a factor; it seems people simply enjoyed the variety more.