Your metabolism spikes after every bout of physical activity. So if you can break up your hour workout into two half-hour chunks, you'll get two spikes instead of one. Your body burns calories at a higher-rate after a workout (sometimes for several hours after), and if you rejuvenate it later in the day, you'll further enhance the effect. This can be taken advantage of in small ways, too. Even two 15-minute walks can cause a boost. So, with both your meals and your workouts, try to go with smaller/shorter but more frequent. Doing cardio is great for you, but doing cardio and lifting weights is even better for burning fat. If you want the most bang for your buck, you should do both. Working with weights is important if you've cut back on calories. When you restrict your caloric intake, you risk losing muscle mass instead of fat.  If so, you might shed some pounds and still not get the results you're looking for. If you're doing both cardio and lifting weights, it's ideal if you do weights first and then do cardio — in other words, “firm then burn!” Doing so helps keep your post-workout metabolism up for longer — perhaps even all day. This order of exercise may also be easier for you to manage. Generally, pumping iron requires better form and technique. When you're tired from running or biking, it may be harder to lift weights with proper technique. This type of exercise routine can help you break up your workout without actually stopping your workout session. Interval training involves you going at an easy pace for a duration of time, and then going all out. You can also adjust the duration and pauses between the cycling back and forth. This can burn more calories and potentially increase your metabolism. The simplest example of interval training might be the treadmill. Walk for 30 seconds, then run full out for 30. Just 15 minutes of this is more beneficial than a 30-minute even-paced jog. Whatever your workout is — whether it's a 15 minute walk with the dog or a 10K through the park — your body gets used to...

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Write a summary of the previous text in Vietnamese:
Chia nhỏ buổi tập. Kết hợp tập sức mạnh với tập cardio. Bắt đầu buổi tập bằng cách tập rèn sức mạnh, sau đó chuyển sang tập aerobic. Thử tập ngắt quãng. Thử bài tập chéo.