Running After Lifting: Benefits, Drawbacks, and Optimizing Your Routine

Is running after lifting bad?

The practice of running after a strength training session is generally not "bad" and can be an effective strategy for many fitness goals, provided the intensity, volume, and individual objectives are carefully considered to mitigate potential interference with specific adaptations.

Understanding Concurrent Training

Concurrent training refers to the practice of combining resistance training and endurance training within the same training cycle, often within the same day or even the same session. For many individuals, incorporating both types of exercise is essential for holistic health and fitness, encompassing strength, cardiovascular health, and body composition. The question of optimal sequencing—whether to lift then run, or run then lift—has been a subject of significant scientific inquiry and practical debate.

The Interference Effect: Myth or Reality?

Historically, concerns about the "interference effect" have suggested that performing endurance training and strength training too closely together could blunt the adaptations from one or both modalities. The primary mechanism proposed for this interference relates to conflicting cellular signaling pathways:

• Resistance training primarily activates pathways like mTOR (mammalian target of rapamycin), which promotes muscle protein synthesis and hypertrophy.
• Endurance training primarily activates pathways like AMPK (AMP-activated protein kinase), which enhances mitochondrial biogenesis and oxidative capacity.

While AMPK activation can, under certain conditions, inhibit mTOR, the degree to which this occurs in practical training scenarios for the average fitness enthusiast or even competitive athlete is highly dependent on the training parameters. Current research suggests that for most individuals, the interference effect is less pronounced than once thought, particularly if the cardio is not excessively intense or prolonged immediately following heavy lifting. Significant interference is more likely to occur with high-volume, high-intensity concurrent training, especially if the goal is maximal strength or power development.

Physiological Considerations

When deciding whether to run after lifting, it's crucial to understand the physiological demands and adaptations associated with each exercise type.

• Energy System Depletion: Resistance training, particularly heavy lifting, primarily relies on the ATP-PCr system and anaerobic glycolysis, depleting muscle glycogen stores. If these stores are significantly depleted, subsequent running performance, especially at higher intensities, may be compromised.
• Hormonal Response: Heavy resistance training elicits an acute anabolic hormonal response (e.g., growth hormone, testosterone). While endurance exercise can elevate cortisol (a catabolic hormone), moderate-intensity cardio performed after lifting is unlikely to significantly negate the anabolic signals from the weight training.
• Neuromuscular Fatigue: Lifting places significant stress on the central nervous system (CNS) and causes peripheral muscle fatigue. Running on fatigued muscles can alter running mechanics, potentially increasing the risk of injury or reducing the quality of the run.
• Acute Performance: Your ability to perform the second exercise type will inevitably be affected by the first. If running is performed after lifting, your running speed, endurance, or perceived effort for a given pace might be compromised compared to running on fresh legs.

Benefits of Running After Lifting

Despite potential concerns, there are several compelling reasons why running after lifting can be a beneficial strategy:

• Enhanced Calorie Expenditure: Combining both modalities in one session increases the total energy expenditure, which can be advantageous for body fat reduction.
• Time Efficiency: For individuals with limited time, consolidating workouts into a single session is a practical solution that allows them to incorporate both strength and cardiovascular training.
• Improved Recovery (Active Recovery): Low-to-moderate intensity cardio performed after a resistance training session can act as an active recovery method, promoting blood flow to fatigued muscles, which may aid in nutrient delivery and waste product removal.
• Cardiovascular Health: Regardless of the order, incorporating both types of exercise provides comprehensive benefits for overall cardiovascular health, improving heart function, blood pressure, and endurance.

Potential Drawbacks and Considerations

While not inherently "bad," running after lifting does come with potential drawbacks, especially depending on your primary fitness goals:

• Compromised Strength/Power Gains: If your primary goal is to maximize strength, power, or muscle hypertrophy, performing high-intensity or high-volume cardio immediately after lifting may slightly blunt these adaptations due to the interference effect and increased systemic fatigue.
• Increased Risk of Overtraining/Injury: Performing two demanding activities back-to-back without adequate recovery or proper progression can increase the risk of overtraining syndrome or acute injuries due to fatigue-induced poor form.
• Suboptimal Performance in the Second Modality: Your running performance will likely be less than optimal if your muscles are already fatigued from lifting. This is a crucial consideration if you are training for a running event or aiming for personal bests in your runs.
• Goal-Specific Prioritization: The order matters significantly if you have highly specific, high-level goals. For example, a powerlifter would prioritize lifting, whereas a marathon runner would prioritize running.

Optimizing Your Workout Order

The decision to run after lifting largely depends on your individual fitness goals, the intensity and volume of each component, and your recovery capacity.

• Prioritize Your Main Goal:
  • Strength/Hypertrophy Focus: If your primary goal is to maximize strength, power, or muscle growth, it is generally recommended to perform your resistance training first. This ensures you are maximally fresh for your most demanding lifts, allowing for optimal neural drive and force production.
  • Endurance Focus: If your main goal is to improve cardiovascular endurance or performance in a running event, it might be more beneficial to perform your running session first.
• Intensity and Volume:
  • Low-to-Moderate Intensity Cardio: If you choose to run after lifting, keep the cardio intensity low to moderate (e.g., steady-state jogging, cycling) and the duration reasonable (20-40 minutes). This minimizes the interference effect and can aid recovery.
  • High-Intensity Cardio: Avoid high-intensity interval training (HIIT) or very long endurance runs immediately after heavy lifting, as this combination is most likely to induce significant fatigue and potential interference.
• Recovery Strategies: Adequate nutrition (especially protein and carbohydrates post-workout), hydration, and sleep are paramount when combining these training modalities to support recovery and adaptation.

Practical Recommendations

1. Lift First for Strength/Hypertrophy: If building muscle or increasing strength is your priority, perform your resistance training session first when you are freshest.
2. Adjust Cardio Intensity: If you run after lifting, opt for low to moderate intensity cardio. This can serve as an effective cool-down or active recovery.
3. Consider Separating Sessions: For competitive athletes or individuals with highly specialized goals (e.g., maximal strength and marathon training), separating resistance and endurance sessions by at least 6 hours (or on separate days) can minimize the interference effect and optimize adaptations.
4. Listen to Your Body: Pay attention to signs of excessive fatigue, persistent soreness, or a decline in performance. These could indicate that your combined training volume or intensity is too high.
5. Fuel Appropriately: Ensure adequate pre-workout nutrition to fuel both activities and immediate post-workout nutrition to kickstart recovery and muscle protein synthesis.

Conclusion

Running after lifting is not inherently "bad" and can be a highly effective and time-efficient strategy for achieving general fitness, improving body composition, and enhancing overall health. The key lies in understanding your primary fitness goals and intelligently structuring your workouts. By prioritizing your main objective, managing the intensity and volume of your cardio, and focusing on recovery, you can successfully integrate both strength and endurance training into a comprehensive and beneficial fitness regimen.