Why Box Squatting for Mobility, Hypertrophy & Strength Developments?

Because ‘Box Squatting’ allows your hips to move through their fullest Range of Motion (R.o.M.) currently accessible when squatting, while maintaining correct joint alignment and stability, and simultaneously fatiguing the muscle sufficiently to elicit a hypertrophic response (muscle growth) throughout the lower body.

For more information on this technique, and the importance of always maintaining, or striving towards, a full Range of Motion (R.o.M.), have a read of my article “Mobility: a free gain of intelligent weight training, an elusive dream in yoga’’

Motor Unit Recruitment & Full Range of Motion

Dr John Rusin argues that loading the body’s joints through their full range of motion (RoM) produces the most optimal muscular reaction within the body.

This hypothesis can be analysed through the use of an Electromyography Assessment (EMG), which calculates the Motor Unit Recruitment (MUR) (the muscle mass utilised during any given motion).

François Billaut of the Victoria University, Australia subsequently tested and confirmed this hypothesis which proved that both high intensity exercises, utilising the body’s full range of motions through each respective joint, produced the largest muscular reaction in the body.

Taking Rusin & Billaut’s work into account, in conjunction with Brad Schoenfeld’s research which highlighted that “intensity (i.e. load)… is arguably the most important exercise variable for stimulating muscle growth’’, we can confirm that it is far more difficult for someone with mobility issues to successfully manage excess body fat, maintain joint integrity and develop adequate muscle mass standards if they cannot access the necessary range of motion in any given exercise (typically squats).

So, practically, how does immobility or bio-mechanical issues impede weight-loss or strength developments?

  • When we look at any given compound exercise in the gym (typically squats), we are looking for a full range of motion to recruit/utilise as many muscles as possible to perform the given exercise.

  • If a client, or trainee cannot access the full range of motion while maintaining correct joint alignment, then the muscles involved cannot be utilised, or fatigued sufficiently or safely to bring about sufficient muscular reaction to cause weight-loss or strength developments.

  • 6 inch box plus 2 red plates

  • 12 inch box plus gray plate

  • 12 inch box plus green plate

  • 12 inch box plus yellow plate

  • 12 inch box plus blue plate

  • 12 inch box plus blue & gray plate

Kubo et. al (2019) examined the muscular impact of different squat depth by examining two different categories of athletes.

  • ​This study compared the effect of squatting with either full depth (140 degrees of knee flexion) or half depth (90 degrees of knee flexion) on muscle volume of the quadriceps, hamstrings, gluteus maximus, and hip adductors.

  • 17 untrained subjects were randomly assigned to the full-squat or half-squat group, and squatted 2 times per week for 10 weeks. Subjects performed 3 sets each session at 80-90% of their 1RM. Training load was progressed by 5kg once subjects could perform 3 sets of 8 reps.

  • The researchers found that the full-squat group experienced significantly greater increases in muscle volume of the glutes and adductors compared to the half-squat group.

Barbell Back Squat

Full Range of Motion (RoM)

Barbell Back Box Squat

Partial Range of Motion (RoM)

So, can immobility impede weight-loss, mobility or strength developments?

  • Forhan & Gill argued that ‘

    • patients with obesity are routinely advised by their health care provider to become more physically active for the purpose of losing weight and reducing cardiovascular and metabolic risk.

    • Although such advice is well intended to promote health and wellness, changes to physical activity levels and the associated benefits are illusive unless issues related to functional mobility are addressed.

    • If a patient with obesity is not able to move around at an intensity and frequency required to lose weight or prevent weight gain they are at greater risk of experiencing mobility issues.

    • Those patients with impaired mobility will continue to experience restrictions in activities at home, work, school and in the community thereby having a negative impact on their health related quality of life (HRQoL).

  • So, short answer: YES

Technique for those who have trouble squatting:

  1. Use a ‘box’ (12 inch plyometric box advised) and additional bumper/olympic plates to create individualised box height.

2. Box height should be 1-4 inches below the bend of the knee (calculated from the back of the leg).

3. Clients who have trouble squatting typically perform better when queued with the following; keep the HEELS slightly outside of the width of the hip and when descending, drive the two knees away from each other first and foremost. This will create both tension and room in the hip joint to perform the exercise.

How do I choose the best height for a box for Squatting?

1: Use a 12 inch plyometric box and additional bumper/olympic plates to create individualised box height.

2. Box height should be 1-4 inches below the bend of the knee (calculated from the back of the leg).

3: Those with poor hip mobility should aim for the height of the box to be 1-2 inches below the bend in the knee (calculated from the back of the leg).

Clients with good hip mobility should aim for 2-4 inches below the bend of the knee.

Long term goal is to no longer need a box for squatting whatsoever.