When you’re strapped for time, trying to carve out 30 minutes five days a week for your workouts can feel like an exercise in just trying not to go crazy. Unless, of course, your boss is cool with you blowing off work, someone else is cleaning your apartment or you suddenly have zero family obligations.
Fortunately, if you bust these six time-wasting fitness myths, you’ll work out smarter, score superior results in less time and give your schedule some much-needed breathing room.
Myth 1: All cardio workouts are created equal.
If you’re going to work out on cardio machines, you’ll get the biggest reward on your time investment with high-intensity intervals like Tabatas. By pushing your body to the max and then recovering, you’ll work all of your body’s energy systems (both aerobic and anaerobic) to speed fat loss. You’ll also make greater gains in your aerobic fitness than you will with steady-state cardio, allowing you to work out harder and longer, explains LA-based personal trainer Mike Donavanik, C.S.C.S., C.P.T.
To perform a Tabata on any machine, work as hard as you can for 20 seconds, recover for 10, and then repeat eight times for a total of four minutes. During each work bout, you should push yourself hard enough that you don’t think you could sustain your pace for even one extra second. As you’ll feel, these sessions are intense, so you’ll only need to perform them two to three times per week, says Noby Takaki, C.S.C.S., performance training manager at the East Bank Club in Chicago.
Myth 2: Always keep your body guessing.
You don’t want your body to plateau, but if you are mixing up every single workout, you are missing out on the fundamental principle of training: progressive overload.
Progressive overload, exercise-science speak for systematically increasing the stress placed on your body during given exercises, allows you to get stronger, faster and fitter. Each workout has to build on the previous one for optimal results, Takaki says.
The solution: craft an exercise plan. Each week or two, focus on lifting slightly heavier weights, running a little faster and moving to advanced progressions of your favorite bodyweight or TRX moves. Having a plan will save you time trying to decide what you’re going to do that day and how much you should lift, Donavanik says.
Myth 3: Cardio is queen.
If, during the after-work gym rush, you manage to find an open treadmill or elliptical, you probably feel pretty lucky. But you’d be wrong. Minute per minute, strength training is better than cardio at preventing added inches around your waist, according to a 2015 Harvard study that followed exercisers over the course of 12 years.
Strength-training’s biggest benefit comes from its ability to increase overall metabolic rate, Takaki says. That’s because your level of lean muscle mass is a primary factor in determining how many calories you burn even when you are not exercising. Perform strength training about three times a week for maximal fat-loss results, she recommends.
Myth 4: You need to perform isolation moves like bicep curls and leg extensions.
There’s nothing wrong with isolation exercises. But when it comes to efficiency, they are pretty “meh.” Besides being largely un-functional — meaning they do not mimic real-life movement patterns — they don’t typically work as many muscles simultaneously as other kinds of movements, like squats or lunges.
However, if you perform large, compound movements that load the body across multiple joints and muscle groups at once, you’ll enjoy a greater caloric burn and increase your heart rate to a greater extent, Donavanik says. Think about it: You could perform glute bridges, leg extensions and leg curls — or you should just do some squats, which work out several muscles at once. Plus, compound exercises tap the body’s fundamental movement patterns to help you get better at running, jumping or just getting your suitcase into overhead airplane storage.
Compound exercises that should be a staple of any woman’s routine include deadlifts, squats, lunges, rows, bench presses and pull-ups.
Myth 5: You need to lift weights for 10+ reps per set.
“The heavier you lift, the more challenging each exercise is going to be, the higher your heart will get elevated, the more calories you will burn both during and after your workout, the more your body composition will improve and the stronger you’ll get, Donavanik says. Plus, it takes a lot less time to lift a weight for six reps as opposed to 12.
For the greatest gains in strength and muscle, focus on getting stronger in set and rep schemes like three sets of eight reps, four sets of six reps and even five sets of two reps. What counts as “heavy” is different for every woman. Select weights that push you, but allow you to maintain perfect form. You should end each set just eeking out the last rep with proper technique, which will prevent exercise injury. Lifting heavy weights doesn’t cause injury, lifting with poor form does.
Myth 6: You need to stretch before your workout.
In one Journal of Strength and Conditioning Research study, exercisers who warmed up with low-intensity leg exercises were able to squat 8.36% more weight during their workout than after performing traditional stretches. That’s because, rather than simply elongating the body’s connective tissues as you do with stretching, dynamic warm-up exercises improve blood flow to your musculature, increase range of motion and prepare your neurological system to properly fire across your muscle cells. As an added bonus, when you skip stretching for a dynamic warm-up, you spend a greater percentage of your time in the gym moving and reaping results, Donavanik says.
Aim for your warm-up to last about 15 minutes and flow seamlessly into your workout by mimicking the moves you’re about to perform during your “actual” workout, Donavanik adds. Great options include squats, lunges, incline pushups, calf raises, butt-kickers, high-knees and side shuffles.
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