Should You Do Cardio Before or After Lifting? Evidence-Based Guide

Many fitness enthusiasts and athletes face the question: when doing both cardiovascular (aerobic) and resistance (weight/lifting) training in the same session (or same day), should cardio come before or after the weights? The intuitive answer often depends on preference or habit. But from a physiological and adaptation standpoint, the order can influence acute performance, interference effects, and long-term gains. In this article, we review the relevant evidence and mechanistic theory, and then discuss practical guidelines.

Concurrent training and the interference effect

First, some background. When aerobic and resistance training are combined (especially in the same session or in close proximity), there is the possibility of a so-called interference effect—i.e., endurance training may dampen gains in strength, power, or hypertrophy compared to resistance training alone. This phenomenon was first documented by Hickson (1980) and has been a recurring topic in exercise science. Many later studies and reviews have explored when and how interference occurs (e.g. GSSI Sports Science Exchange, “Using Nutrition and Molecular Biology to Maximize Concurrent Training”) Gatorade Sports Science Institute.

However, the interference is not inevitable or uniform. Its magnitude depends on variables such as volume, intensity, training status, recovery, nutrition, and the ordering of modalities. Some meta-analyses suggest that concurrent training has more negative impacts on explosive power than on hypertrophy or strength per se (i.e. the interference is more severe for speed/power outcomes) Live Science.

Thus, when asking “cardio before or after weights?”, one of the key concerns is which order minimizes interference while maximizing performance and adaptation.

Acute performance: immediate effects of order on strength vs endurance

From an acute (within-session) standpoint, the order often affects how well you can perform each modality.

• If you do intense cardio first, you may deplete muscle glycogen, induce fatigue, impair neuromuscular performance, and reduce maximal strength or volume in the subsequent weight session. Some observational and experimental studies suggest that prior endurance work can blunt strength or muscle power performance.
• Conversely, if you perform resistance training first, you might compromise the quality or total work you can do in the cardio portion (especially if it is high intensity), due to fatigue or metabolic stress.

For example, in a study by Silva et al. (cited in some summary sources), performing strength training prior to endurance leads to reduced time-to-exhaustion in subsequent endurance exercise compared to endurance alone, indicating that strength before cardio impairs endurance performance (i.e. lower endurance capacity) PMC.

Another acute study (Shirai et al., in animal muscle) found that doing resistance first then endurance activates certain molecular signaling (mTOR) better than the reverse order, which hints at differential influences on adaptation signaling depending on order PMC.

Thus, the immediate trade-off is: doing cardio first may reduce strength output; doing weights first may reduce cardio output, particularly for high-intensity or endurance goals.

Molecular and signaling considerations: mTOR, AMPK, and cross-talk

To get deeper, one must consider intracellular molecular signaling. Two major pathways are often implicated:

• mTOR (mechanistic target of rapamycin): a central regulator of protein synthesis, hypertrophy, and anabolic signaling
• AMPK (AMP-activated protein kinase): a “cellular energy sensor” activated under energetic stress, promoting catabolic and energy-generating pathways

The canonical model suggests that high metabolic stress or high AMPK activation can inhibit or downregulate mTOR signaling, thus interfering with muscle-building responses. As endurance or aerobic exercise tends to elevate AMPK, there is the theoretical possibility that prior cardio could blunt the mTOR-driven anabolic response to resistance training (i.e., a molecular interference) Gatorade Sports Science Institute+2ScienceDirect+2.

However, in practice, many studies show that the molecular “interference” is weak or inconsistent. For instance, Jones et al. (2021) found that the intensity of aerobic exercise (moderate vs high) did not significantly diminish anabolic signaling (mTOR phosphorylation) after resistance exercise in endurance-trained individuals. In some cases, mTOR signaling was even greater when preceded by moderate aerobic work. This suggests that the interference might not be as strong as once thought under many real-world scenarios Nature.

Furthermore, Shirai et al. (2020) observed that the order (resistance → endurance vs endurance → resistance) modified mTOR signaling in mice, with resistance-first generally more favorable for anabolic activation PMC.

Overall, molecular theory supports the idea that heavy or exhaustive cardio prior to weights is more likely to impair anabolic responses, but in many realistic training settings, that interference may be modest or negligible given appropriate recovery, nutrition, and training design.

Adaptation over time: what do intervention studies and meta-analyses show?

In the long term, what matters is not just the acute session but how cumulative adaptations (strength, hypertrophy, aerobic capacity, metabolic health) are impacted by order.

Some relevant evidence:

• Jerrican Tan et al. (2023) investigated combining aerobic and heavy resistance training and found that both body composition and muscle hypertrophy improved in both groups (resistance-only and combined), and they did not find a clear superiority of one sequence over another—i.e. combining aerobic + resistance did not clearly hamper hypertrophy when done appropriately. PMC+1
• A systematic review comparing aerobic training vs resistance training in older adults showed that aerobic training is superior for improving VO₂max and reducing body weight, while resistance is superior for lean body mass; this underscores that both modalities have distinct adaptation niches, but it does not directly address order within a session. ScienceDirect
• In a meta‐analysis of concurrent training, a short-term effect size advantage for lower-body strength was found when strength was performed before endurance (vs the reverse) Gatorade Sports Science Institute+1
• A 2025 review on muscle fatigue and interference (Denadai et al., 2025) further underlines that the way concurrent training is organized (e.g., order, recovery, intensity) can modulate the interference, emphasizing that fatigue management is vital. ScienceDirect

Thus, while combining modalities is generally feasible and beneficial, ordering strength before cardiovascular work tends to yield a modest advantage for strength/hypertrophy outcomes in many studies.

Goals matter: which order to choose depending on your priorities

Because the optimal order depends heavily on one’s primary goals, here’s a conceptual guideline:

1. Primary goal = strength, muscle growth, or power
   If your focus is on maximizing hypertrophy, strength, or explosive output, then it is generally better to do resistance training first, when your neuromuscular system is fresh and energy stores (glycogen, etc.) are intact. Doing heavy cardio right beforehand may reduce your ability to recruit maximal loads, reduce volume, or blunt anabolic signaling.
2. Primary goal = endurance, cardiovascular fitness, or performance in aerobic sport
   If your target is to improve VO₂max, aerobic capacity, or performance in a race/event, then doing cardio first may give you a better quality cardio session (less fatigue), and preserve your ability to execute high-intensity intervals, tempo runs, or long efforts without prior fatigue.
3. Goal = fat loss / general fitness / health
   When both are relevant (as is common for general fitness), the difference is often smaller, and the priority may fall to which you want to emphasize or the order that ensures you don’t skip one. Some literature and popular advice lean toward doing strength first to “save enough energy” for weights, preventing cardio from undermining strength gains. Some newer studies even suggest doing weights before cardio may yield slightly better fat loss outcomes (e.g., greater visceral fat reduction) (though these are preliminary). The Jerusalem Post+1
4. Mixed or equal priority
   If you care about both equally, a pragmatic approach is to alternate the order across training days or to separate cardio and resistance into different sessions (e.g., morning vs afternoon or on different days) when possible, to reduce interference.

Warm-up vs full cardio: nuance in what “cardio first” means

It’s important to distinguish doing a warm-up cardio (e.g. 5–10 minutes light-to-moderate work) versus performing a full-fledged aerobic training session (e.g. 20–40 min steady or high-intensity work). Many guidelines recommend a light cardiovascular warm-up before weights, purely for raising temperature, increasing blood flow, and priming the muscles and joints. The Mayo Clinic, for example, recommends 5–10 minutes of low- to moderate-intensity aerobic activity as a warm-up before strength training. Mayo Clinic

Doing so is unlikely to impair strength outcomes, because the metabolic load is modest. The interference concerns mainly arise when that prior cardio is of moderate-to-high duration or intensity.

Practical considerations: fatigue, volume, recovery, nutrition

Even with good theoretical support, practical issues can override ideal order. A few considerations:

• Fatigue and form. When you begin a resistance session fatigued (from cardio), your form may degrade, increasing injury risk or reducing effectiveness.
• Volume/quality trade-off. If doing both in one session, there may be trade-offs: doing more cardio might force you to reduce weight, sets, or rest in the lifting portion, and vice versa.
• Recovery time. The longer the rest between cardio and resistance, the less direct the interference; separating the modalities by hours or doing them on alternate days helps reduce overlap in metabolic stress.
• Nutrition and fueling. Adequate carbohydrate intake before and between sessions helps maintain glycogen and reduce AMPK activation due to low energy state, thereby supporting mTOR signaling and recovery. The GSSI article suggests consuming leucine-rich protein soon after resistance and spacing nutrients appropriately to optimize both endurance and strength adaptation. Gatorade Sports Science Institute
• Training status. Beginners or recreational trainees often experience interference less severely; in highly trained athletes, responses may differ.
• Intensity control. If cardio is moderate rather than exhaustive, the interference is less likely.

Summary comparison: pros and cons

Here’s a table summarizing pros/cons of cardio-first vs weights-first:

Order	Pros	Cons
Cardio → Weights	Better quality cardio when fresh; good for endurance focus	May impair strength/power volume; more interference risk
Weights → Cardio	Preserves strength performance; may modestly favor hypertrophy	Cardio output might suffer; fatigue may reduce endurance work

In most combined sessions where strength/hypertrophy is a priority, doing weights first edges out as the more conservative choice to protect strength output and anabolic signaling.

Real-world caveats and context

• Many studies use trained or semi-trained individuals, controlled protocols, or muscle biopsies; real-world gym-goers may respond differently.
• Interference effects tend to be more pronounced when volume, intensity, or frequency of endurance training is high.
• Some newer data challenge the dogma of interference, and suggest that under moderate doses and ample recovery, combining both modalities even in the same session is effective without large downsides.
• The absolute difference in adaptation between orders, for many people, may be modest—consistency, progression, nutrition, sleep, and recovery still matter more.

Recommendations

Based on the literature and practical constraints, here are actionable recommendations:

1. Align order with priority
   • If strength, hypertrophy, or power is your goal, do weights first.
   • If endurance performance is your goal, do cardio first.
2. Use a light warm-up cardio, not full cardio
   A modest 5–10 min warm-up is generally safe before lifting. The trade-offs concern doing a substantial cardio block first.
3. If possible, separate sessions or days
   Doing cardio and resistance in different sessions (morning/evening) or separate days reduces proximal interference.
4. Manage intensity and volume
   Avoid doing maximal or exhaustive cardio immediately before weights. Adjust volume so you can still perform your strength work well. Use lower-intensity cardio if placing it before lifting.
5. Optimize nutrition
   Consume carbohydrates and protein to support glycogen replenishment and muscle protein synthesis. Avoid training in a severely depleted state whenever strength matters.
6. Periodize and vary order
   You can periodically swap orders or give “priority” weeks to strength or endurance to avoid stagnation.
7. Listen to your body and monitor progress
   If you notice strength decreasing or undue fatigue, adjust order, separation, or volume.

Final thoughts

In sum, the science suggests that doing resistance training before cardio is often the safer bet when strength, hypertrophy, or power are important goals, because it helps preserve performance and anabolic signaling. Doing cardio first may slightly impair strength outcomes, especially when cardio is intense or prolonged. However, the magnitude of interference is usually modest under reasonable training loads, and many people can combine both effectively if they manage fatigue, nutrition, and recovery well.

About the Author

Lucas Silveira

Administrator

Visit Website View All Posts