Bodyweight Exercise Resistance: Understanding Load in Pull-Ups, Push-Ups, and Crunches

What is the weight or resistance used in doing pull ups or push ups or crunches?

The "weight" or resistance in bodyweight exercises like pull-ups, push-ups, and crunches is not a fixed external load but rather a percentage of your own body mass, dynamically determined by leverage, body position, and the specific mechanics of the movement.

Understanding Bodyweight Resistance

Unlike exercises performed with barbells, dumbbells, or resistance machines where the load is explicitly stated, bodyweight exercises utilize your own mass as the primary form of resistance. The effective weight or load experienced by your muscles during these movements is a fraction of your total body weight, influenced by biomechanical principles such as leverage, center of gravity, and the angle of your body relative to gravity. This effective load can vary significantly not only between different exercises but also within variations of the same exercise.

Understanding Resistance in Push-Ups

Push-ups are a foundational upper body pushing exercise. The resistance encountered is a percentage of your body weight that your upper body must push against gravity.

• Standard Push-Up: In a standard push-up position (hands shoulder-width apart, body straight, feet on the floor), approximately 60-75% of your total body weight is typically borne by your hands. The exact percentage varies based on individual limb lengths and body proportions.
• Incline Push-Up: When your hands are elevated (e.g., on a bench or wall), you are performing an incline push-up. This decreases the effective resistance because a larger portion of your body weight is supported by your feet, and the angle reduces the gravitational pull on your upper body. The higher the incline, the less resistance.
• Decline Push-Up: Elevating your feet (e.g., on a box or bench) increases the effective resistance. This shifts more of your body weight onto your upper body, making the exercise more challenging and increasing the percentage of body weight your arms must push.
• One-Arm Push-Up: This advanced variation dramatically increases the resistance, as nearly 100% of your effective body weight (minus the weight of the supporting arm) must be lifted by a single arm.

Understanding Resistance in Pull-Ups

Pull-ups are a challenging upper body pulling exercise that typically involves lifting a substantial portion of your body weight against gravity.

• Standard Pull-Up: When performing a standard pull-up, you are lifting nearly your entire body weight. The effective resistance is very close to 100% of your total body weight, as your arms are supporting and pulling your entire mass (minus the small weight of your forearms and hands that are gripping the bar).
• Assisted Pull-Ups: Using resistance bands, a pull-up assist machine, or a spotter significantly decreases the effective resistance. The assistance helps to counteract a portion of your body weight, making the movement easier. The thicker the band or the more assistance provided, the less body weight you are lifting.
• Weighted Pull-Ups: Adding an external load (e.g., a weight vest, a dumbbell between your feet, or plates attached to a dip belt) increases the resistance beyond 100% of your body weight, making the exercise more demanding.

Understanding Resistance in Crunches

Crunches are an abdominal exercise focusing on spinal flexion. The resistance in crunches is primarily the weight of your upper torso and head, leveraged against gravity.

• Standard Crunch: In a standard crunch (lying supine, feet on the floor, lifting head and shoulders off the ground), the effective resistance is significantly less than your total body weight. It's essentially the weight of your upper body segment that you are lifting against gravity. This load is often estimated to be around 20-40% of your total body weight, as your hips and lower back remain on the ground, and the lever arm for the abdominal muscles is relatively short.
• Variations:
  • Hands behind head: While often perceived as adding resistance, this primarily changes leverage and can place undue strain on the neck if not performed correctly. The actual weight lifted doesn't change much.
  • Weighted Crunches: Holding a weight plate on your chest or behind your head directly increases the external resistance your abdominal muscles must overcome.
  • Incline Crunches: Performing crunches on a decline bench increases the resistance by increasing the range of motion and the gravitational pull on your upper body.

Modifying Resistance in Bodyweight Exercises

A key advantage of bodyweight training is the ability to progressively overload or regress exercises without external equipment, primarily by manipulating leverage and stability.

• Increasing Resistance (Making it Harder):

  • Change Leverage: Elevate feet (decline push-ups), reduce base of support (one-arm push-ups, one-leg squats).
  • Add External Load: Wear a weight vest, hold dumbbells (for squats/lunges), use a dip belt (for pull-ups/dips).
  • Increase Range of Motion: Perform exercises on elevated surfaces (e.g., push-ups with hands on parallettes to go deeper).
  • Slow Down Tempo: Increase time under tension.
  • Decrease Stability: Perform exercises on unstable surfaces (e.g., TRX push-ups) or with fewer points of contact.
  • Progress to Advanced Variations: Transition from regular push-ups to plyometric push-ups or from pull-ups to L-sit pull-ups.

• Decreasing Resistance (Making it Easier):

  • Change Leverage: Elevate hands (incline push-ups), use assistance (band-assisted pull-ups, assisted squats).
  • Reduce Range of Motion: Perform partial repetitions.
  • Increase Stability: Use a wall or sturdy object for support.
  • Regress to Easier Variations: Transition from regular push-ups to kneeling push-ups or from pull-ups to inverted rows.

The Importance of Progressive Overload with Bodyweight

Regardless of the specific percentage of body weight used, the principle of progressive overload remains crucial for continuous strength gains and muscle adaptation. For bodyweight exercises, this means:

• Increasing Repetitions and Sets: Performing more reps or sets over time.
• Decreasing Rest Time: Reducing the time between sets.
• Improving Form and Control: Executing movements with greater precision and muscle engagement.
• Progressing to Harder Variations: Moving to more challenging versions of an exercise (e.g., from incline push-ups to standard push-ups, then to decline push-ups).
• Adding External Load: Once bodyweight variations become too easy, external resistance can be added.

Conclusion

The "weight" or resistance in bodyweight exercises is a dynamic and adaptable component of your own body mass, influenced by biomechanics. Understanding how leverage and body position affect the effective load empowers you to intelligently modify these exercises to match your current strength level and progressively challenge your muscles for continued growth and adaptation. By mastering these principles, you can effectively utilize your own body as a versatile and powerful training tool.