Before you start your muscle-building workout season, consult a doctor. Muscle-building exercises are highly demanding to your body, and people with some chronic illnesses (such as cardiac conditions, high blood pressure, or stroke) may not be candidates for this type of workout. If you have high blood pressure (hypertension) you should not do heavy weightlifting without consulting your doctor. If your blood pressure is above 180/110 mm Hg, do not lift weights until you have normalized your blood pressure with medications. Strength training engages the muscles in your body and makes them work against a resistance. When you make your muscles work against a resistance, you are forcing your muscle fibers to respond to the added stress which leads to enhanced muscle size and definition. In order to build muscle, you need to add strength (also called resistance) training to your weekly routine.  Typical strength training programs use free weights (dumbbells, barbells), exercise machines, elastic tubing, or even just the body weight (pushups, pull-ups, crunches). Plan a balanced, total body  strength training program to build the muscles in your body (see third section). Muscle building is not fat burning. The best way to add muscle mass is weight training, while the way to get rid of muscles is extended cardio (you've never seen a Marathon runner with big muscles, have you?).  However, you should not forget cardio exercises entirely as these strengthen your cardiorespiratory system and have numerous other health benefits, including improving bone strength, reducing blood pressure, reducing risk of chronic illnesses (diabetes, cancer, cardiovascular conditions), and improved mood. Also keep in mind that reducing overall body fat with cardio can cause muscles to "pop," and your body can look leaner and stronger. The key when planning cardio routine during muscle-building season is to do shorter sprints instead of long, aerobic workouts. Focus on 20 minute high-intensity exercises with 30 to 60 second high-intensity...

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Write a summary of the previous text in Vietnamese:
Tham khảo ý kiến của huấn luyện viên và/hoặc bác sĩ. Lên kế hoạch thực hiện bài tập tăng cường sức mạnh cơ bắp. Không nên tập quá nhiều bài tập tim mạch (cardio). Nghỉ ngơi thật nhiều. Tìm hiểu về kỹ thuật chính xác và hiểu rõ về rủi ro.