Let's start with some good news: At least a third of Americans are now getting the government-recommended 2½ hours weekly of  heart pumping cardio, along with a couple of  strength-training sessions weekly.

The bad news is, many of  us are allowing sloppy or lazy habits to sabotage our efforts. Some are tied to the latest technology for tracking and monitoring our every move and morsel of food. Others are old, reliable mistakes that have been undermining health and fitness forever.

Here are a eight exercise mistakes to correct right now.

1. You put too much trust in calorie-couting wearables.

Yes, keeping track of your caloric intake and output is helpful when you're trying to shed a few pounds, but don't make it an obsession when you're exercising. For one thing, it's been well documented that the accuracy of the calorie counters on wearables is variable — and can be off by as much as 15 to 60 percent.

2. You try to spot-reduce. 

Sorry. It's impossible.  Even doing thousands of crunches a day will not give you six-pack abs.  Wrapping your waist in plastic won't do it, either. In order to lose those love handles, you'll need to watch what you eat. That's right. Abs are primarily cooked up in the kitchen. Pay close attention to the quality and the quantity of the foods you eat.  Until you tighten your diet, you won't see one ripple — much less getting ripped.

3. You skip strength training. 

Many women, especially, fall into the trap of only doing cardio, because they erroneously believe they will "bulk up" if they pick up a weight.  But 99.9 percent of women simply don't have enough testosterone to make that happen. What's a much bigger issue for women's health is losing our muscle strength.  And if you want a tight, toned body, strength training is a must.

4. You do the minimum but expect that maximum results.

What you put in to your exercise regimen is what you'll get out. If your goal is to look like an Olympic athlete, you'll likely need to make exercise a full-time job (like they do). That's unreasonable for most people. But so is hoping to trim and tone by downloading the latest app.

5. You are always connected.

You can barely get a workout in because you're constantly talking, texting, or taking selfies.  Do yourself and your workout a favor, and disconnect while you sweat.

6. Your form is poor.

Day in and day out, you are exercising, but unbeknownst to you, your form is horrible — and may be doing yourself more harm than good.  Always try to exercise in front of a mirror to check your posture and form.  And learn to do each excercise properly.

For example, when doing biceps curls, don't use momentum to swing the weights. You want to control the movement. Stand with your knees slightly bent and your spine in neutral, with your dumbbells at your sides and your elbows in. Then slowly curl the weights up until your forearms kiss your biceps and slowly lower them to the starting position.

7. You do the same old, same old. 

Many people get stuck in a workout rut, but your body won't change if you don't. If you never adjust the duration, intensity, sets, reps, weight, or exercises, you will surely hit a plateau. If you've been running the same 5 miles on the treadmill for the past five months or five years, try sprucing up your routine by doing wind sprints instead, or mixing things up with an interval program.

8. You ignore injuries and pain. 

In a word: don't.  If you have any pain — particularly if it's sharp or chronic — you should probably see a doctor. Pain is your body's signal for help. Sure, it might be nothing. But why chance it?