Static Stretching Between Sets: Performance Impact, Research, and Practical Recommendations

Should you static stretch between sets?

While static stretching between sets may acutely increase range of motion, current evidence largely advises against it during resistance training sessions due to potential reductions in strength, power, and overall performance.

Introduction

The practice of stretching has long been a cornerstone of fitness, often associated with injury prevention and improved performance. However, the timing and type of stretching have become subjects of extensive scientific scrutiny. One specific area of debate among fitness enthusiasts and professionals is the utility of static stretching between sets of resistance training. This article, grounded in exercise science and biomechanics, will dissect the evidence to provide a clear, actionable answer to this common question.

Understanding Static Stretching

Static stretching involves extending a muscle and holding it at its maximum comfortable length for a sustained period, typically 15 to 60 seconds. The goal is to gradually lengthen muscle fibers and connective tissues, thereby increasing flexibility and range of motion (ROM) around a joint. While effective for improving long-term flexibility, its acute effects on the body are what dictate its appropriateness during a workout.

The Conventional Wisdom: Pre-Workout Stretching

Historically, static stretching was a ubiquitous component of pre-workout routines. The belief was that it would prepare muscles for activity and prevent injury. However, a wealth of contemporary research has challenged this notion. Studies have consistently shown that prolonged static stretching before resistance training or power-based activities can acutely decrease strength, power output, and jump height. This performance impairment is attributed to several factors, including:

• Altered Muscle-Tendon Unit Stiffness: Static stretching can reduce the stiffness of the muscle-tendon unit, which diminishes its ability to store and release elastic energy efficiently.
• Reduced Neural Excitability: Prolonged stretching can decrease the excitability of the motor neurons, leading to a temporary reduction in the central nervous system's ability to activate muscle fibers effectively.
• Changes in Muscle Architecture: Some research suggests stretching can temporarily alter fascicle length and pennation angle, which may impact force production.

The Case Against Stretching Between Sets

Extending the findings from pre-workout stretching, similar concerns arise when considering static stretching between sets:

• Acute Performance Impairment: Just as with pre-workout stretching, performing static stretches between sets can acutely reduce the strength and power output of the stretched muscles in subsequent sets. This means you might lift less weight, perform fewer repetitions, or execute movements with less explosive power.
• Increased Fatigue: Holding a static stretch, especially for a significant duration, can induce localized fatigue in the stretched muscle. This can compromise your ability to perform the next set effectively and contribute to overall workout fatigue.
• Time Inefficiency: Resistance training sessions are often structured for optimal work-to-rest ratios. Spending valuable recovery time on static stretching takes away from active recovery or mental preparation for the next set, potentially hindering overall workout efficiency.
• Compromised Stability: While stretching aims to increase ROM, excessive or ill-timed stretching can transiently reduce joint stability, especially if the muscles responsible for stabilizing the joint are over-lengthened.

The Potential Benefits: Limited Evidence and Specific Contexts

While the general consensus leans against static stretching between sets, it's important to consider specific, albeit limited, contexts where it might be considered:

• Targeted Flexibility Improvement: If a lifter's primary goal for a specific session or exercise is to acutely increase range of motion (e.g., to achieve deeper squat depth or improve shoulder mobility for overhead lifts) and they are willing to accept a potential trade-off in strength/power for that set, then very targeted, short-duration static stretching might be employed. However, this is a highly individualized strategy and not a general recommendation.
• Injury Rehabilitation (Under Supervision): In a therapeutic setting, under the guidance of a physical therapist, specific static stretches might be prescribed between sets for targeted muscle groups to address flexibility deficits crucial for recovery. This is distinct from general fitness training.
• "Stretch-Mediated Hypertrophy" Theory: Some emerging research (primarily animal studies) suggests that muscles stretched under load might experience greater hypertrophy due to mechanical tension and cellular signaling. However, this concept often refers to sustained loaded stretching or extreme ranges of motion during an exercise, rather than traditional static stretching between sets. Human evidence supporting static stretching between sets for superior hypertrophy is currently weak or inconclusive.

What the Research Says

Numerous studies have investigated the acute effects of static stretching on performance parameters. The overwhelming majority conclude that static stretching performed immediately before or during a resistance training session can negatively impact maximal strength, power, and muscular endurance. The duration of the stretch appears to be a key factor, with longer holds (e.g., >30 seconds) showing more pronounced detrimental effects. While the exact mechanisms are still being explored, the consensus in exercise science is that for performance-oriented resistance training, static stretching between sets is generally counterproductive.

Practical Recommendations for Training

Based on current scientific understanding, here are practical recommendations regarding static stretching and resistance training:

• Prioritize Dynamic Warm-ups: Before your workout, engage in dynamic stretches and mobility drills that mimic the movements you'll be performing. This effectively prepares your muscles and nervous system without impairing performance.
• Perform Static Stretching Post-Workout: The ideal time for static stretching is after your resistance training session, when your muscles are warm, or on separate dedicated flexibility days. This allows you to focus on increasing long-term flexibility without compromising acute performance.
• Focus on Active Recovery Between Sets: During your rest periods between sets, prioritize active recovery. This might involve light walking, gentle joint rotations, or simply focusing on breathing, which can aid in lactate clearance and maintain readiness for the next set.
• Consider Mobility Drills, Not Static Stretches: If you feel restricted in a specific movement, incorporate targeted mobility drills (e.g., cat-cow for spinal mobility, hip circles) before or during your warm-up, rather than sustained static stretches between working sets.

Alternatives to Static Stretching Between Sets

Instead of static stretching, consider these evidence-based alternatives for optimizing your workout and recovery:

• Dynamic Stretching: Incorporate movements like leg swings, arm circles, torso twists, and walking lunges during your warm-up to improve blood flow, activate muscles, and increase joint range of motion.
• Foam Rolling/Self-Myofascial Release: Using a foam roller or massage ball can help address muscle stiffness and trigger points, potentially improving tissue quality and range of motion without the performance drawbacks of static stretching. This can be done before or after your workout, or even between sets for specific, tight areas, but should not replace your rest period.
• Active Recovery: Light cardio or movement between sets can help maintain blood flow and facilitate recovery, preparing you for the next set without negatively impacting muscle performance.
• Dedicated Flexibility Sessions: Schedule separate sessions focused solely on flexibility and mobility, allowing you to perform static stretches without the immediate concern of performance impairment in resistance training.

Conclusion and Key Takeaways

While the pursuit of flexibility is a valuable component of overall fitness, the timing and type of stretching are critical. For individuals engaged in resistance training with goals of maximizing strength, power, or hypertrophy, static stretching between sets is generally not recommended. The potential for acute performance decrements outweighs any perceived benefits for most lifters. Prioritize dynamic warm-ups, perform static stretching post-workout or on separate days, and utilize active recovery or foam rolling between sets to optimize your training outcomes. Always align your stretching practices with your specific fitness goals and current scientific understanding.