The Benefits of Getting a Full Stretch During Resistance Training

Resistance training is a cornerstone of fitness, but how you perform each movement can dramatically impact your results. One often overlooked yet highly effective technique is achieving a full stretch during resistance training exercises. Fully stretching the target muscle at the end of its range of motion engages more muscle fibers, enhances flexibility, and maximizes muscle growth.

1. Increased Muscle Activation and Growth

When you perform a resistance exercise with a full stretch, you engage the muscle through its entire range of motion (ROM). Studies show that training through a full ROM leads to greater muscle activation compared to partial ROM exercises.

  • Why It Works: Stretching a muscle under tension creates more microtears in the muscle fibers, which are essential for muscle repair and growth. Research has also shown that a fully stretched position increases mechanical tension, one of the primary drivers of hypertrophy.
  • Scientific Evidence: A 2021 study published in Sports Medicine found that resistance training with a full ROM resulted in significantly greater increases in muscle size compared to partial ROM training. (Pinto et al., 2021)

2. Enhanced Flexibility and Mobility

Resistance training often gets a bad reputation for "tightening" muscles, but incorporating a full stretch during movements can actually improve flexibility over time. When you stretch a muscle under load, you lengthen the connective tissues, improving their elasticity.

  • Practical Example: In exercises like Romanian deadlifts, reaching a full stretch in the hamstrings not only strengthens the muscles but also enhances hamstring flexibility, reducing the risk of injury.
  • Scientific Evidence: A study in the Journal of Strength and Conditioning Research (2019) demonstrated that resistance training with a focus on the full stretch improved joint mobility and muscle flexibility more effectively than static stretching alone. (Schoenfeld & Grgic, 2019)

3. Greater Muscle Pump and Blood Flow

Achieving a full stretch during resistance training can lead to an enhanced muscle pump by increasing blood flow to the working muscles. This is particularly noticeable in exercises like chest flyes or preacher curls, where holding a stretch momentarily allows for maximum blood flow to the target area.

  • Why It Matters: Increased blood flow delivers more oxygen and nutrients to the muscle, supporting recovery and growth. The stretch also activates the sarcoplasmic component of the muscle, contributing to the "pumped" look.
  • Scientific Evidence: Research published in Physiology Reports (2016) found that stretching muscles under load enhances vascular function and stimulates muscle growth by increasing cellular hydration. (Dankel et al., 2016)

4. Improved Strength Through Full Range of Motion

Training with a full stretch helps build strength across the entire ROM, not just in the middle or top of the lift. This has functional benefits, as strength improvements become more transferable to real-life activities and athletic performance.

  • Practical Example: In squats, going deep into the stretch phase (below parallel) activates glutes and hamstrings more effectively, leading to greater strength development in these muscle groups.
  • Scientific Evidence: A 2014 study in The Journal of Applied Physiology highlighted that full ROM training led to greater strength gains in comparison to partial ROM training, particularly in multi-joint exercises like squats and bench presses. (McMahon et al., 2014)

5. Reduced Risk of Injury

A full stretch not only activates more muscle fibers but also strengthens the connective tissues (like tendons and ligaments) around the joint. Over time, this enhanced joint stability can reduce the risk of injury during both training and everyday activities.

  • Why It Works: Stretching under load teaches your muscles and connective tissues to handle tension in vulnerable positions, preparing them to resist strain.
  • Scientific Evidence: A review in Sports Health (2020) concluded that resistance training, when performed with a full stretch, decreases the likelihood of injury by improving joint integrity and muscle balance. (Behm et al., 2020)

How to Incorporate a Full Stretch in Resistance Training

Here are some tips to ensure you’re getting the most out of the full stretch in your exercises:

  1. Focus on Form: Prioritize proper technique over lifting heavier weights. Poor form can limit your ROM and increase injury risk.
  2. Control the Eccentric Phase: Lower the weight slowly to maximize the stretch at the bottom of the movement.
  3. Pause at the Stretch: Hold the stretch position for 1-2 seconds to increase tension and engage more muscle fibers.
  4. Target Stretch-Intensive Exercises: Incorporate movements like Romanian deadlifts, chest flyes, preacher curls, and deep squats into your routine for maximum stretch benefits.

Why Full Stretching Matters

Incorporating a full stretch during resistance training is a simple yet powerful way to enhance your results. From increasing muscle growth and flexibility to improving strength and reducing injury risk, the benefits of stretching under tension are well-supported by science. While it requires focus and control, this approach can elevate your training and help you achieve greater results over time.

References:

  1. Pinto, R. S., et al. (2021). "Range of motion in resistance training: The impact on muscle development and strength." Sports Medicine.
  2. Schoenfeld, B. J., & Grgic, J. (2019). "Effects of resistance training on flexibility." Journal of Strength and Conditioning Research.
  3. Dankel, S. J., et al. (2016). "Stretch-mediated hypertrophy and vascular adaptations with resistance training." Physiology Reports.
  4. McMahon, G. E., et al. (2014). "Impact of range of motion on strength and hypertrophy outcomes in resistance training." The Journal of Applied Physiology.
  5. Behm, D. G., et al. (2020). "The role of resistance training in injury prevention." Sports Health.