Slackers can't hide

Pesky fitness experts are a lot like your mother -- they know immediately when you're slacking off. If they're truly invested in improving your fitness level, they'll inspire you to stop doggin' it and start diggin' in.

Here are telltale signs of a slacker, according to a handful of fitness professionals:

• Your expression -- there's a slacker's "when is lunch" look versus a more appropriate "fighting your way through class" look, says Burr Leonard, founder of the Bar Method.
• Bad form is common among slackers, says Tim Rochford, self-defense instructor.
• The fake breath -- when you dramatically puff out your cheeks and blow out hard on exhale, you probably don't want to do the push-ups, says Erin O'Brien, creator of Strong Body, Ageless Body and Complete Pregnancy Fitness DVDs.
• Reading on a cardio machine, says Michele Katz -- NYC health and wellness consultant and personal trainer.
• Cutting back -- when clients are shortening the number and/or length of their workouts or come to the session with reasons why they need to leave early, says Sylvia Orizaba, founder of Body Empowered Fitness.

Hey, I occasionally read on the elliptical and it's no slacker workout! But I'm definitely not working out as hard as when I'm running and unable to scan the page. What are the clues you'd rather be in a hammock than at the gym?