It's a bad habit for a lot of us to breathe at the top of our lungs. Don't do it! Make sure your breaths are deep and coming in through your nose and out slowly through your mouth. Insufficient breathing can wear out your muscles before they wear out themselves. Try to get into a rhythm while you're running. Take a breath for every 3 or 4 steps. Staying in sync will give you something to concentrate on, too. To get your muscles ready to turn into speed machines, you gotta warm up. If you don't, you risk asking them to do things they're not ready to do -- and they'll revolt by ripping and tearing. So do some jumping jacks, some burpees, high knees, butt kicks, and get your body loose and ready. Cool down after your workouts, too, with a good stretching session. This'll help bring your heart rate down and get your head back down from the rush you've just had, in addition to keeping your muscles safe and not freezing back up. Improper form is not only potentially dangerous, but it wastes energy needlessly. To hit that 6-minute mile, you need to be running as efficiently as possible. Here's the gist:  For your upper body, make sure you are looking forward on the horizon and not to either side. Keep your shoulders loose -- if you notice they're stiff, give 'em a quick shake to rid yourself of the tension. Keep your back straight and your elbows at a 90-degree angle, hands in loose fists. For your lower body, make sure you're hitting the ground lightly (quieter = quicker) with your mid-foot, rolling onto your toes and propelling forward. Lift your knees slightly, keep your strides short, and your feet landing directly beneath you. Aim to feel as if you're springing off the ground. ork out your arms, legs, and core. Since so much of a good mile time is about strength, working out your body is useful, too. Include squats, lunges, planks, sit ups, and push-ups into your regimen to keep your muscles primed for optimal performance. Incorporate work with free weights into your routine as well. Do bicep curls, tricep...

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Write a summary of the previous text in Chinese:
了解正确的呼吸方式。 记得一定要热身以及冷却。 学着用正确的姿势跑步。 锻炼手臂、双腿，以及核心肌群。 确保摄取充足的水分。 跑前（或者跑后）要吃好。 减肥。 买一双优质的跑鞋。