Leg Press: Assessing 70 kg, Factors, and Proper Technique

Is 70 kg Leg Press Good?

70 kg on the leg press can be a good starting point or a solid working weight, but its "goodness" is entirely relative to an individual's strength, training experience, body composition, and specific fitness goals, always prioritizing proper form and the type of leg press machine used.

Understanding "Good": A Contextual Approach

In the realm of strength training, labeling a specific weight as "good" is inherently subjective and often misleading without context. A 70 kg leg press might be an impressive feat for a novice, a moderate warm-up for an experienced lifter, or an appropriate working weight for someone focusing on muscular endurance. The effectiveness and appropriateness of any weight are determined by how it aligns with your individual physiology, training history, and objectives.

Factors Influencing Leg Press Performance

Several critical factors dictate whether 70 kg is an appropriate or challenging weight for your leg press.

• Individual Strength Levels and Training History: A person new to resistance training will find 70 kg significantly more challenging than someone who has been consistently lifting for years. For a true beginner, even just the weight of the sled (often 30-50 kg empty) can be a challenge. For an intermediate lifter, 70 kg might be a working set for higher repetitions or a lighter load for recovery.
• Bodyweight and Body Composition: Strength is often best assessed relative to bodyweight. A 70 kg leg press for someone weighing 50 kg is proportionally much heavier than for someone weighing 100 kg. While leg press isn't a direct measure of functional strength like a squat, your body's overall mass and composition influence your ability to move the sled.
• Training Goals (Strength, Hypertrophy, Endurance):
  • Strength: Typically involves heavier loads for fewer repetitions (e.g., 1-5 reps). If 70 kg allows you only 1-5 reps with maximal effort, it's a strength-building load for you.
  • Hypertrophy (Muscle Growth): Often uses moderate loads for moderate repetitions (e.g., 6-12 reps). If 70 kg allows you 6-12 reps with good form and challenging effort, it's suitable for hypertrophy.
  • Endurance: Involves lighter loads for higher repetitions (e.g., 15+ reps). If 70 kg feels light enough to perform many repetitions, it could be used for endurance, though lighter weights are usually more common here.
• Proper Form and Technique: The weight is irrelevant if your form is compromised. Lifting 70 kg with poor technique (e.g., rounding your lower back, knees caving in, limited range of motion) is not "good" and significantly increases injury risk while diminishing muscle activation.
• Repetition Range and Set Structure: Is 70 kg for a single repetition maximum (1RM)? Or is it for 10 repetitions? The difficulty changes drastically. A 70 kg 1RM is very different from doing 3 sets of 10 repetitions at 70 kg.
• Leg Press Machine Type: This is a crucial distinction.
  • 45-Degree Sled Leg Press (most common): Due to the angle, you are pushing against gravity and the friction of the sled. 70 kg on this machine will feel significantly lighter than 70 kg on a horizontal machine because you are not lifting the full 70 kg straight up. The effective resistance is the weight of the sled plus the added plates, multiplied by the sine of the angle (approx. 70% of the total weight).
  • Horizontal (Seated) Leg Press: In this machine, the weight stack is typically connected via cables, and you are pushing horizontally. The resistance listed is usually the actual weight being moved. 70 kg on a horizontal leg press will generally feel much heavier than 70 kg on a 45-degree sled leg press for the same individual. Our discussion primarily assumes the more common 45-degree sled leg press unless specified.

How to Assess Your Leg Press Strength

To determine if 70 kg is "good" for you, you need to assess your current strength and how it relates to your goals.

• One-Rep Max (1RM) Testing: This is the maximum weight you can lift for a single, perfect repetition. If 70 kg is close to your 1RM, it indicates significant strength for that weight. However, 1RM testing is advanced and carries a higher risk of injury; it should only be performed by experienced lifters with proper spotting.
• Repetition Max (RM) for Specific Goals: A safer and more practical approach is to find your RM for your target repetition range.
  • For strength, find a weight you can lift for 3-5 reps with good form.
  • For hypertrophy, find a weight you can lift for 8-12 reps with good form.
  • For endurance, find a weight you can lift for 15-20+ reps with good form. If 70 kg fits comfortably into one of these ranges while providing a challenging stimulus, it's an appropriate weight for that goal.
• Relative Strength Metrics: While not as commonly used for leg press as for squats, you can compare your leg press weight to your bodyweight. For instance, being able to leg press 1.5-2 times your bodyweight for 6-10 reps on a 45-degree sled is often considered a good benchmark for intermediate lifters.

Setting Appropriate Leg Press Goals

Your goals should be progressive and individualized, not fixed on an arbitrary number like 70 kg.

• Beginner Considerations: For those new to the leg press, focus on mastering the movement pattern with light weight or even just the empty sled. Once form is solid, gradually increase the weight. A reasonable initial goal might be to comfortably press your bodyweight for 8-12 repetitions on a 45-degree machine.
• Intermediate and Advanced Benchmarks: As you progress, you can aim for higher relative strength. For a 45-degree leg press:
  • Intermediate: 1.5-2x bodyweight for 6-10 reps.
  • Advanced: 2.5-3x bodyweight or more for 6-10 reps. These are general guidelines; individual mechanics and limb lengths can influence performance.
• Progression Principles: To continue making progress, adhere to the principle of progressive overload. This means gradually increasing the demands on your muscles over time by:
  • Increasing the weight (e.g., from 65 kg to 70 kg).
  • Increasing the number of repetitions with the same weight.
  • Increasing the number of sets.
  • Decreasing rest times between sets.
  • Improving technique to allow for heavier loads.

The Importance of Proper Leg Press Technique

No weight, regardless of how "good" it seems, is worth sacrificing proper form. Incorrect technique can lead to injury and negate the benefits of the exercise.

• Setup and Foot Placement:
  • Sit with your back firmly pressed against the pad, hips stable.
  • Place your feet shoulder-width apart in the middle of the footplate, ensuring your heels are flat. Adjust height so knees are roughly in line with ankles.
  • Unlock the safety catches.
• Movement Execution (Eccentric and Concentric Phases):
  • Eccentric (Lowering): Slowly lower the weight by bending your knees, allowing them to track directly over your toes. Lower until your knees are close to your chest, forming roughly a 90-degree angle or slightly deeper, without your lower back lifting off the pad.
  • Concentric (Pushing): Drive through your heels and the midfoot to push the weight back up. Extend your legs fully but avoid "locking out" your knees at the top to maintain tension and protect your joints.
• Common Mistakes to Avoid:
  • Rounding the Lower Back: This is the most critical mistake, putting immense stress on the lumbar spine. Ensure your hips stay firmly planted.
  • Knees Caving In (Valgus Collapse): Keep your knees tracking over your toes throughout the movement.
  • Partial Range of Motion: Not lowering the weight sufficiently limits muscle activation.
  • Lifting Heels Off the Plate: This shifts stress to the knees and reduces glute/hamstring engagement.
  • Locking Out Knees: Fully extending and locking the knees at the top can strain the knee joint. Maintain a slight bend.

Beyond the Numbers: Holistic Leg Development

While the leg press is an excellent exercise for building quadriceps, gluteal, and hamstring strength, it's part of a larger picture of lower body development. Incorporate a variety of exercises for balanced strength, mobility, and injury prevention.

• Compound Exercises: Include movements like squats (barbell, goblet, dumbbell), lunges, and deadlifts (conventional, Romanian) to work your legs and posterior chain in a more functional, multi-joint manner.
• Unilateral Work: Exercises like split squats, lunges, and single-leg RDLs address muscular imbalances between your legs and improve stability.
• Mobility and Flexibility: Regular stretching and mobility work for your hips, knees, and ankles will enhance your range of motion and improve your ability to perform exercises effectively and safely.

Conclusion: Is 70 kg Leg Press Good for YOU?

Ultimately, 70 kg on the leg press is "good" if it represents a challenging yet manageable weight that allows you to perform the exercise with perfect form, aligning with your current strength level and training goals. It's not about comparing yourself to others or arbitrary numbers but about consistent, safe, and effective progression relative to your starting point. Focus on technique, listen to your body, and progressively challenge yourself, and any weight that helps you achieve your fitness objectives will be "good."