A 90-minute workout routine can improve your fitness, but it can also do more harm than good if you overdo it. Performing only one or two exercises, such as using a cardio machine or lifting heavy weights for 90 minutes, can stress your body and create injuries. Breaking your long workouts into several routines that focus on different aspects of fitness will help you get the most out of your exercise routines.
Performing a repetitive motion for long periods, whether it's during one workout, on consecutive days or several times per week, can cause overuse and repetitive-stress injuries. Jogging on a treadmill, for example, is high impact and can create stress on your hips, ankles, knees and lower back. Using a rowing machine for 90 minutes requires you to use your shoulders, back, hips and knees in a strenuous way that can cause degradation of ligaments, tendons and joints. Continuing to lift heavy weights after you've created the beneficial micro tears in muscle fibers that help build muscles might cause excessive muscle damage that delays the repair and regrowth process.
Types of Fitness
When you exercise, you can improve your aerobic and anaerobic capacity and stamina, build muscle and improve muscular endurance. You do this by using different levels of intensity for different periods. For example, you'll perform aerobic exercises at longer, steadier periods of intensity than you will for anaerobic training, which consists of short, high-intensity bursts of activity. To build muscle, you'll use higher loads and perform fewer reps, the opposite method you'll use to build muscular endurance. The American College of Sports Medicine recommends 150 minutes of moderate-intensity exercise per week, which should include cardio and some resistance for best results.
90-Minute Workout Elements
Create 90-minute workouts that begin with some resistance training and end with cardio work. Starting with resistance exercises helps you deplete stores of glycogen so that you'll burn fat more efficiently during cardio exercises, according to certified strength and conditioning specialist Stew Smith. If you're a beginner, start with 15 minutes of dumbbell or resistance band exercises, using about half the maximum resistance you can use. Perform an exercise for 30 seconds at a moderate intensity, take a short break, then move to a new exercise. If you're in better shape, use more resistance or perform 60-second sets and expand your resistance training to 20 minutes or longer. After resistance training, perform aerobic exercise for 30 to 45 minutes, changing the type of exercise you do every 10 to 15 minutes. This could include moving from a treadmill to an elliptical to an exercise bike to a rowing machine. You can run stairs, jump rope or dance to create cardio exercises. Add intervals to your cardio work, going at a high intensity for 30 to 60 seconds, then recovering at a walking pace for two or more minutes. Your workout should include 10 to 15 minutes of warming up, cooling down and stretching.
If you work out every day or every other day, don't follow the same routine each time. Vary your equipment, exercises and the types of exercise you do. You might emphasize aerobic exercise for 60 minutes one day, with less-intense resistance training or a core workout. You might start with 30 minutes of heavy weightlifting followed by cardio exercise at the low end of your aerobic heart rate range, followed by some core exercises and a longer stretch.
Start every workout with five minutes of pre-exercise warmup. At a moderate intensity, skip in place and swing your arms, perform jumping jacks and butt kicks and move your body in ways that gradually increase your breathing, circulation and heart rate. After you finish your workout, take five minutes to lower your breathing, circulation and heart rate with slow walking or other low-intensity movements. Stretch all of your muscles, holding each stretch just past your comfortable range of motion for 20 seconds.