Here are some new “fitness rules” – based on the latest science - to help you get in shape and lose weight:

Rule #1: It’s okay to exercise ALONE. According to personal trainer Jonathan Ross, the only time having a “workout buddy” helps is if you exercise with someone who’s more fit and focused than you are. Then you’ll be motivated to push yourself harder to keep up. But if you exercise with someone who just wants to chat and gossip, Ross says it’ll distract you, and compromise your workout.

Fitness rule #2: Remember that intensity is more important than frequency. That comes from exercise scientist Dr. Wayne Westcott. He says we should never exercise the same muscles every day, especially after an intense workout. Because muscles need time to repair torn-down tissue, otherwise we risk injury. So, if you’re worn out from lifting weights, for example, Dr. Westcott says let your arms rest for at least two days, and focus on other parts of your body like running to improve your cardio.

One more fitness rule: The best exercise DOESN’T happen at the gym. To stay slim, experts say we need to stay active all day. In fact, a new study found that people who rarely go to the gym, but are active most of the day, tend to live longer compared to people who hit the gym every day, but then spend the rest of their time sitting at a desk, or on the couch. In other words, doing lots of little things, like walking during our lunch break, or standing while we’re on the phone, makes a big difference to our health.