The order in which cardio and strength training are performed has been a subject of debate among fitness enthusiasts and professionals. This article aims to explore the physiological and performance implications of doing cardio before or after strength training. By understanding the effects on muscle strength, endurance, body composition, and overall fitness goals, individuals can make more informed decisions about structuring their workouts.
Cardiovascular exercise (cardio) and strength training are both essential components of a well-rounded fitness program. Cardio, such as running, cycling, or swimming, primarily targets the cardiovascular system, improving heart and lung function, and burning calories. Strength training, on the other hand, focuses on building and maintaining muscle mass, increasing bone density, and enhancing muscular strength and endurance. The question of whether to perform cardio before or after strength training has significant implications for maximizing the benefits of each type of exercise and achieving specific fitness goals.
Physiological Effects of Cardio and Strength Training
Cardio
During cardio exercise, the body’s demand for oxygen increases, leading to an elevation in heart rate and breathing rate. This aerobic activity primarily utilizes the oxidative energy system, which burns a combination of carbohydrates and fats for fuel. Prolonged cardio sessions can improve cardiovascular endurance, increase the efficiency of the heart and lungs, and enhance the body’s ability to transport and utilize oxygen.
Strength Training
Strength training involves short bursts of intense muscular contractions. It mainly targets the anaerobic energy system, which relies on stored ATP and phosphocreatine for immediate energy and then shifts to anaerobic glycolysis. This type of training stimulates muscle fiber hypertrophy (growth), increases muscle strength and power, and can also have beneficial effects on bone health.
Cardio Before Strength Training
Fatigue and Performance Impact
Performing cardio before strength training can lead to pre-existing fatigue in the muscles and cardiovascular system. For example, a long run before hitting the weights may cause a decrease in muscle strength and power output during the strength training session. The depletion of glycogen stores during cardio can also affect the intensity and volume of strength training that can be effectively performed. Studies have shown that individuals who perform moderate to high-intensity cardio prior to strength training experience a reduction in the number of repetitions and the amount of weight they can lift compared to when they perform strength training first.
Hormonal Changes
Cardio can also cause hormonal changes that may not be favorable for strength training. Extended cardio sessions can increase the levels of stress hormones such as cortisol. Elevated cortisol levels can have a catabolic effect on muscle tissue, potentially leading to muscle breakdown. This is counterproductive to the anabolic goals of strength training, which aim to build and maintain muscle mass.
Metabolic Rate
While cardio does increase the metabolic rate during the exercise itself, the post-exercise increase in metabolic rate (known as excess post-exercise oxygen consumption or EPOC) is generally lower compared to strength training. If the goal is to maximize the overall calorie burn and increase metabolic rate over an extended period, starting with cardio may not be the most effective approach.
Cardio After Strength Training
Muscle Building and Recovery
Performing strength training first allows for maximal effort and intensity during the muscle-building phase. After strength training, the muscles are primed for repair and growth. Adding cardio after strength training can then take advantage of the elevated metabolic rate and hormonal environment created by the strength workout. The increase in blood flow during cardio can also aid in the removal of waste products such as lactic acid from the muscles, potentially reducing muscle soreness and promoting faster recovery.
Fat Burning
Strength training depletes glycogen stores in the muscles. When cardio is performed after strength training, the body is more likely to rely on fat as a fuel source. This is because the glycogen levels are lower, and the body needs to access alternative energy stores. This can enhance the fat-burning effect of the overall workout, which is beneficial for individuals looking to improve body composition and lose body fat.
Cardiovascular Benefits
Although strength training itself has some cardiovascular benefits, adding cardio after strength training can further enhance cardiovascular fitness. It allows for a comprehensive workout that targets both muscular and cardiovascular systems, improving overall endurance and health.
Considerations for Different Fitness Goals
Bodybuilding and Muscle Gain
For individuals focused on bodybuilding and maximizing muscle growth, it is generally recommended to perform strength training first. This ensures that the muscles are fresh and able to perform at their highest intensity during the strength exercises. Cardio can then be added after strength training, but it should be of a moderate intensity and duration to avoid excessive interference with muscle recovery and growth. For example, a short 20-30 minute session of low-intensity cardio such as walking on a treadmill or using a stationary bike can be sufficient.
Weight Loss and Fat Burning
If the primary goal is weight loss and fat burning, the order may depend on individual preferences and fitness levels. However, performing strength training first followed by cardio can be advantageous. As mentioned earlier, this sequence can enhance the fat-burning effect during the cardio session due to depleted glycogen stores. Additionally, strength training helps to preserve muscle mass, which is important for maintaining a higher metabolic rate during a calorie-restricted diet. For those who have lower fitness levels or are new to exercise, starting with a short, low-intensity cardio warm-up before strength training may be beneficial to prepare the body for the more intense strength exercises.
Endurance Training and Athletic Performance
For endurance athletes, such as runners or cyclists, incorporating both cardio and strength training is crucial. The order may vary depending on the specific training phase and goals. During the off-season or base training, strength training first followed by cardio can help improve overall strength and power, which can translate into better endurance performance. However, during the competitive season, the focus may shift more towards maintaining cardiovascular fitness, and the order may be adjusted accordingly. For example, a short, high-intensity strength training session followed by a longer cardio session may be appropriate to simulate the demands of a race.
Conclusion
The decision of whether to do cardio before or after strength training depends on various factors, including individual fitness goals, fitness levels, and personal preferences. Performing cardio before strength training can lead to fatigue and potential negative impacts on strength and muscle growth due to hormonal changes and glycogen depletion. On the other hand, performing strength training first and then cardio can enhance muscle building, fat burning, and overall fitness. It is important for individuals to consider their specific goals and experiment with different workout sequences to determine what works best for them. Additionally, proper nutrition and recovery strategies are essential regardless of the order of exercise to support muscle repair, growth, and overall health. By understanding the physiological effects and making informed decisions about the order of cardio and strength training, individuals can optimize their workouts and make significant progress towards their fitness goals.
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