Doing 100 crunches a day practically guarantees flat abs
Crunches improve one abdominal muscles' strength and endurance (if you do a lot of them) But ultimately, your body fat level dictates whether or not your abs are flat. For well-rounded fitness and balance, you should work all the muscles in your abs, core and back. Planks are one exercise that can target a range of ab muscles.
Skip weights and do only cardio if weight loss is your goal.
Weight training is a must if you want to lose body fat and keep it off. Resistance training helps preserve lean muscle tissue during calorie deficits, which you have to achieve if you are going to lose fat over any length of time. Since muscle burns more calories at rest, weight training also boosts calorie burning even when you're not working out.
If you don't sweat a lot you didn't work out hard enough
How much you sweat depends on the type of workout and your training goal rather than how hard you're working. Power lifters tend not to sweat as much at those who do a high-intensity interval workout. Your environment influences how much you'll sweat. Cooler temperatures and lower humidity result in less sweating. Plus, some people simply sweat more than others.
You should be sore the next day after a good workout
Soreness occurs when you are first starting a program, changing a workout or increasing the amount of weight or number of exercises you are doing. You don't have to feel sore each time you work out in order to train properly. Also, you're not likely allowing yourself enough recovery time if you're sore on a regular basis.
Exercising smarter makes your limited workout time more productive and safer. Ditch the myths and keep the facts.
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