# A Multi-Experiment Investigation of the Effects Stance Width on the Biomechanics of the Barbell Squat

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## Abstract

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## 1. Introduction

#### 1.1. Rationale

#### 1.2. Aims

#### 1.3. Hypotheses

## 2. Materials and Methods

#### 2.1. Ethical Approval

#### 2.2. Experiment 1

#### 2.2.1. Participants

#### 2.2.2. Procedure

#### 2.2.3. Squat Protocol

#### 2.2.4. Processing

^{2}) of the barbell during the ascent phase of the squat was quantified. The maximum extent to which the knee translated both anteriorly and laterally during the squat was calculated using the Visual3D. These net distances were normalized to the length of the shank and expressed as a percentage (%) [17].

#### 2.2.5. Statistical Analyses

#### 2.3. Experiment Two

#### 2.3.1. Participants

#### 2.3.2. Procedure

#### 2.3.3. Squat Protocol

#### 2.3.4. Processing

#### 2.3.5. Statistical Analyses

## 3. Results

#### 3.1. Experiment 1

#### 3.1.1. Kinetic and Temporal Variables

_{(95% C.I. = 0.19–0.94)}, t = 3.06, p = 0.002) and NARROW (β = 0.52

_{(95% C.I. = 0.21–0.82)}, t = 3.36, p = 0.001), conditions (Table 1). In addition, the medial GRF impulse during the descent phase was significantly larger in the WIDE, in relation to the MID (β = 0.57

_{(95% C.I. = 0.19–0.94)}, t = 2.00, p = 0.04) and NARROW (β = 0.39

_{(95% C.I. = 0.04–0.79)}, t = 2.71, p = 0.006), conditions (Table 1). Finally, the angle of the GRF vector was significantly larger in the NARROW (β = 2.67

_{(95% C.I. = 0.94–4.40)}, t = 3.10, p = 0.002) and MID (β = 2.99

_{(95% C.I. = 0.89–5.09)}, t = 2.87, p = 0.003) conditions, compared to the WIDE stance width (Table 1).

_{(95% C.I. = 1.58–14.40)}, t = 2.51, p = 0.016) condition and, conversely, the energy produced at the knee was significantly greater in the NARROW, compared to the MID (β = 7.52,

_{(95% C.I. = 1.33–13.71)}, t = 2.45, p = 0.018), condition group (Table 1).

#### 3.1.2. Muscle Forces

_{(95% C.I. = 2.29–31.04)}, t = 2.33, p = 0.02) compared to the NARROW (Table 2). Similarly, the hamstring force at mid-lift was significantly larger (β = 15.19

_{(95% C.I. = 1.74–28.64)}, t = 2.26, p = 0.02) in the WIDE condition, compared to the NARROW (Table 3). The hamstring impulse during the ascent phase was significantly (β = 6.30

_{(95% C.I. = 1.05–11.54)}, t = 2.41, p = 0.01) larger in the WIDE condition in relation to the NARROW (Table 4). In addition, the hamstring impulse during the descent phase was significantly (β = 6.86

_{(95% C.I. = 1.91–11.80)}, t = 2.78, p = 0.005) greater in the WIDE condition in relation to the NARROW (Table 2).

_{(95% C.I. = 0.37–4.66)}, t = 2.35, p = 0.02) larger in the WIDE condition in relation to the NARROW (Table 2). The soleus force at mid-lift was significantly (β = 2.74

_{(95% C.I. = 1.33–5.35)}, t = 2.11, p = 0.04) larger in the WIDE condition in relation to the NARROW (Table 4). Finally, the soleus impulse during the ascent phase was significantly (β = 2.47

_{(95% C.I. = 0.27–4.67)}, t = 2.25, p = 0.03) larger in the WIDE condition in relation to the NARROW (Table 2). In addition, the gastrocnemius force at mid-lift was significantly (β = 0.65

_{(95% C.I. = 0.08–1.22)}, t = 6.25, p = 0.031) larger in the WIDE condition in relation to the NARROW (Table 3). Finally, the gastrocnemius impulse during the ascent phase was significantly (β = 9.76

_{(95% C.I. = 6.23–13.29)}, t = 6.25, p < 0.001) larger in the WIDE condition in relation to the NARROW (Table 2).

#### 3.1.3. Kinematics

_{(95% C.I. = 0.03–8.64)}, t = 2.01, p = 0.04) and NARROW (β = 7.48

_{(95% C.I. = 2.52–12.44)}, t = 3.07, p = 0.007) conditions (Table 3). In addition, the ankle eversion at mid-lift was significantly larger in the MID (p = 0.01) and NARROW (p = 0.008) conditions, compared to the WIDE (Table 4). Finally, the ankle rotation at mid-lift was significantly (β = 4.45

_{(95% C.I. = 1.77–7.13)}, t = 3.33, p = 0.003) more externally rotated in the WIDE condition compared to the NARROW (Table 4).

#### 3.2. Experiment 2

#### 3.2.1. Kinetic and Temporal Variables

_{(95% C.I. = 0.03–0.09)}, t = 4.66, p = 0.002) and WIDE (β = 0.10

_{(95% C.I. = 0.05–0.15)}, t = 4.88, p = 0.001) conditions. The angle of the GRF vector was larger in the NARROW condition in relation to the MID (β = 3.29

_{(95% C.I. = 2.17–4.40)}, t = 6.64, p < 0.001) and WIDE (β = 6.31

_{(95% C.I. = 4.89–7.74)}, t = 10.01, p < 0.001) conditions, and also in the MID condition (β = 3.03

_{(95% C.I. = 2.11–3.94)}, t = 7.50, p < 0.001) compared to the WIDE (Table 4). The anterior knee displacement was greater in the NARROW (β = 4.42

_{(95% C.I. = 1.06–7.78)}, t = 2.97, p = 0.02) and MID (β = 4.58

_{(95% C.I. = 2.92–6.23)}, t = 6.27, p < 0.001) conditions compared to the WIDE (Table 3). The lateral knee displacement was greater in the NARROW compared to the MID (β = 2.80

_{(95% C.I. = 0.83–4.77)}, t = 3.22, p = 0.011) and WIDE (β = 8.14

_{(95% C.I. = 5.47–10.82)}, t = 6.89, p < 0.001) conditions, and in the MID compared to the WIDE (β = 5.34

_{(95% C.I. = 2.88–7.81)}, t = 4.91, p = 0.001) (Table 4).

_{(95% C.I. = 0.07–0.21)}, t = 4.36, p = 0.002) condition compared to the NARROW (Table 4). Also, the ascent time was larger in the WIDE compared to the NARROW (β = 0.09

_{(95% C.I. = 0.05–0.12)}, t = 5.53, p < 0.001) and also the MID compared to the NARROW (β = 0.04

_{(95% C.I. = 0.07–0.21)}, t = 3.16, p = 0.01) conditions (Table 4).

_{(95% C.I. = 0.86–2.48)}, t = 4.65, p = 0.001) and WIDE (β = 1.67

_{(95% C.I. = 0.79–2.10)}, t = 5.04, p = 0.001) conditions. The peak vertical GRF was significantly larger in the NARROW compared to the WIDE (β = 0.56

_{(95% C.I. = 0.25–0.87)}, t = 4.08, p = 0.003) condition (Table 3). The vertical GRF impulse during the ascent phase was larger in the WIDE condition compared to the NARROW (β = 0.54

_{(95% C.I. = 0.23–0.86)}, t = 3.91, p = 0.004) (Table 3). The medial GRF impulse during the ascent phase was larger in the WIDE condition in relation to the MID (β = 0.59

_{(95% C.I. = 0.47–0.72)}, t = 10.97, p < 0.001) and NARROW (β = 1.03

_{(95% C.I. = 0.89–1.17)}, t = 16.36, p < 0.001) conditions, and also in the MID condition (β = 0.44

_{(95% C.I. = 0.32–0.55)}, t = 8.40, p < 0.001) compared to the NARROW (Table 3). The medial GRF impulse during the descent phase was larger in the WIDE condition in relation to the MID (β = 0.67

_{(95% C.I. = 0.47–0.87)}, t = 7.61, p < 0.001) and NARROW (β = 1.20

_{(95% C.I. = 0.96–1.45)}, t = 11.04, p < 0.001) conditions, and also in the MID condition (β = 0.53

_{(95% C.I. = 0.39–0.67)}, t = 8.79, p < 0.001) compared to the NARROW (Table 3).

_{(95% C.I. = 0.65–3.91)}, t = 3.16, p = 0.012) and NARROW (β = 3.71,

_{(95% C.I. = 1.31–6.11)}, t = 3.49, p = 0.007) conditions (Table 4). The percentage of energy produced at the knee was significantly greater in the NARROW compared to the MID (β = 1.98,

_{(95% C.I. = 0.23–2.56)}, t = 2.56, p = 0.031) and WIDE (β = 2.84,

_{(95% C.I. = 0.72–4.96)}, t = 3.03, p = 0.014) conditions (Table 3).

#### 3.2.2. Muscle Forces

_{(95% C.I. = 0.29–5.93)}, t = 2.50, p = 0.03) and WIDE (β = 6.61

_{(95% C.I. = 3.59–9.62)}, t = 4.96, p = 0.001) conditions, and also in the MID condition (β = 3.49

_{(95% C.I. = 1.78–5.21)}, t = 4.61, p = 0.001) compared to the WIDE (Table 5). In addition, the quadriceps force at mid-lift was larger in the NARROW (β = 8.70

_{(95% C.I. = 5.35–12.05)}, t = 5.87, p < 0.001) and MID (β = 6.03

_{(95% C.I. = 2.02–9.97)}, t = 3.45, p = 0.007) conditions compared to the WIDE (Table 5).

_{(95% C.I. = 0.42–9.62)}, t = 2.47, p = 0.04) and NARROW (β = 5.86

_{(95% C.I. = 0.54–11.17)}, t = 2.49, p = 0.03) conditions (Table 5). The gluteal force at mid-lift was larger in the WIDE condition in relation to the MID (β = 4.30

_{(95% C.I. = 0.79–7.81)}, t = 2.77, p = 0.02) and NARROW (β = 5.93

_{(95% C.I. = 0.37–11.49)}, t = 2.41, p = 0.04) conditions (Table 5). The gluteal impulse during the ascent phase was significantly larger in the WIDE condition in relation to the MID (β = 2.06

_{(95% C.I. = 0.06–4.05)}, t = 2.33, p = 0.04) and NARROW (β = 2.74

_{(95% C.I. = 1.00–4.48)}, t = 3.57, p = 0.006) (Table 5).

_{(95% C.I. = 2.25–14.33)}, t = 3.10, p = 0.01) and NARROW (β = 9.48

_{(95% C.I. = 2.69–16.27)}, t = 3.16, p = 0.01) conditions (Table 5). The hamstring force at mid-lift was larger in the WIDE condition in relation to the MID (β = 7.25

_{(95% C.I. = 2.71–11.79)}, t = 3.61, p = 0.006) and NARROW (β = 9.90

_{(95% C.I. = 2.30–17.49)}, t = 2.95, p = 0.02) conditions (Table 5). The hamstring impulse during the ascent phase was significantly larger in the WIDE condition in relation to the MID (β = 3.78

_{(95% C.I. = 0.65–6.92)}, t = 2.73, p = 0.02) and NARROW (β = 5.14

_{(95% C.I. = 2.60–7.68)}, t = 4.59, p = 0.001) (Table 5). The hamstring impulse during the descent phase was significantly larger in the WIDE condition in relation to the NARROW (β = 7.32

_{(95% C.I. = 0.82–13.81)}, t = 2.55, p = 0.03) (Table 5).

_{(95% C.I. = 0.16–1.13)}, t = 3.00, p = 0.02) (Table 5). The gastrocnemius force at mid-lift was larger in the NARROW (β = 0.65

_{(95% C.I. = 0.08–1.22)}, t = 2.56, p = 0.03) and MID (β = 0.78

_{(95% C.I. = 0.37–1.19)}, t = 4.26, p = 0.002) conditions compared to the WIDE condition (Table 5)

_{(95% C.I. = 0.34–2.41)}, t = 3.01, p = 0.02) (Table 5). The soleus force at mid-lift was larger in the NARROW (β = 1.38

_{(95% C.I. = 0.16–2.61)}, t = 2.54, p = 0.03) and MID (β = 1.66

_{(95% C.I. = 0.78–2.54)}, t = 4.30, p = 0.002) conditions compared to the WIDE conditions (Table 5).

#### 3.2.3. Kinematics

_{(95% C.I. = 0.96–3.44)}, t = 4.00, p = 0.003) and NARROW (β = 2.83 (95% C.I. = 0.76–4.91), t = 3.09, p = 0.01) conditions (Table 6). The hip abduction ROM was larger in the NARROW compared to the MID (β = 1.79

_{(95% C.I. = 0.87–2.71)}, t = 4.41, p = 0.002) and WIDE (β = 3.86

_{(95% C.I. = 2.38–5.34)}, t = 5.91, p < 0.001) conditions, and also in the MID compared to the WIDE (β = 2.07

_{(95% C.I. = 0.83–3.31)}, t = 3.79, p = 0.004) condition (Table 6). The hip peak internal rotation was larger in the WIDE compared to the MID (β = 2.85

_{(95% C.I. = 1.39–4.30)}, t = 4.43, p = 0.002) and NARROW (β = 5.50

_{(95% C.I. = 3.06–7.93)}, t = 5.10, p = 0.001) conditions, and also in the MID compared to the NARROW (β = 2.64

_{(95% C.I. = 1.31–3.99)}, t = 4.48, p = 0.002) condition (Table 6). The hip internal rotation ROM was larger in the WIDE compared to the MID (β = 4.23

_{(95% C.I. = 2.20–6.27)}, t = 4.71, p = 0.001) and NARROW (β = 7.43

_{(95% C.I. = 3.51–11.35)}, t = 4.29, p = 0.002) conditions, and also in the MID compared to the NARROW (β = 3.19

_{(95% C.I. = 0.85–5.54)}, t = 3.09, p = 0.01) condition (Table 6).

_{(95% C.I. = 2.90–8.28)}, t = 4.70, p = 0.001) and MID (β = 4.14

_{(95% C.I. = 2.36–5.92)}, t = 5.27, p = 0.001) conditions compared to the WIDE condition (Table 6). The knee flexion ROM was larger in the NARROW (β = 9.18

_{(95% C.I. = 3.93–14.43)}, t = 3.96, p = 0.003) and MID (β =

_{7.95 (95% C.I. = 5.03–10.88)}, t = 6.15, p < 0.001) conditions compared to the WIDE condition (Table 6).

_{(95% C.I. = 0.84–3.86)}, t = 3.51, p = 0.007) and WIDE (β = 8.23

_{(95% C.I. = 6.73–9.74)}, t = 12.41, p < 0.001) conditions, and also in the MID condition (β = 5.89

_{(95% C.I. = 4.80–6.98)}, t = 12.25, p < 0.001) compared to the WIDE condition (Table 6). In addition, the ankle dorsiflexion ROM was significantly larger in the NARROW (β = 5.88

_{(95% C.I. = 3.12–8.64)}, t = 4.81, p=0.001) and MID (β = 5.26

_{(95% C.I. = 3.72–6.82)}, t = 7.68, p < 0.001) conditions compared to the WIDE condition (Table 6). The eversion angle at mid-lift was significantly larger in the NARROW condition compared to the WIDE (β = 5.69

_{(95% C.I. = 0.99–10.39)}, t = 2.74, p = 0.02) condition (Table 6). The external rotation angle at mid-lift was significantly larger in the WIDE condition in relation to the MID (β = 3.13

_{(95% C.I. = 0.94–5.33)}, t = 3.23, p = 0.01) and NARROW (β = 6.29

_{(95% C.I. = 3.52–9.06)}, t = 5.14, p = 0.001) conditions, and also in the MID condition (β = 3.16

_{(95% C.I. = 2.25–4.07)}, t = 7.88, p < 0.001) compared to the NARROW (Table 6).

## 4. Discussion

## 5. Conclusions

## Supplementary Materials

## Author Contributions

## Funding

## Informed Consent Statement

## Conflicts of Interest

## References

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**Figure 1.**(

**a**) Experimental marker locations and (

**b**) trunk, pelvis, thigh, shank, and foot segments, with segment co-ordinate system axes (R = right and L = left), (TR = trunk, P = pelvis, T = thigh, S = shank, and F = foot), (X = sagittal, Y = coronal, and Z = transverse planes).

**Table 1.**Kinetic and temporal parameters (mean ± SD) from experiment one as a function of each stance-width group.

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Medial GRF ascent impulse (N/kg·s) | 1.35 | 0.45 | 1.30 | 0.38 | 1.87 | 0.62 |

Medial GRF descent impulse (N/kg·s) | 1.28 | 0.48 | 1.32 | 0.44 | 1.72 | 0.65 |

Hip energy (%) | 36.01 | 13.74 | 32.99 | 9.72 | 40.98 | 9.71 |

Knee energy (%) | 54.13 | 11.40 | 58.99 | 10.50 | 51.47 | 8.93 |

GRF vector angle from the horizontal (°) | 87.01 | 2.46 | 87.33 | 2.09 | 84.34 | 3.50 |

Legend: GRF = ground reaction force |

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Gluteus descent impulse (N/kg·s) | 8.52 | 3.02 | 9.61 | 2.26 | 11.03 | 4.35 |

Peak hamstring force (N/kg) | 37.60 | 20.80 | 46.58 | 23.06 | 54.26 | 28.97 |

Hamstring ascent impulse (N/kg·s) | 16.38 | 6.38 | 19.38 | 8.25 | 22.68 | 11.08 |

Hamstring descent impulse (N/kg·s) | 15.39 | 5.93 | 18.05 | 6.35 | 22.25 | 10.49 |

Hamstring force at mid-lift (N/kg) | 36.17 | 20.14 | 44.26 | 21.66 | 51.36 | 26.79 |

Gastrocnemius ascent impulse (N/kg·s) | 5.89 | 2.07 | 4.88 | 1.83 | 4.75 | 1.67 |

Gastrocnemius force at mid-lift (N/kg) | 6.64 | 2.37 | 5.74 | 2.13 | 5.36 | 2.10 |

Soleus ascent impulse (N/kg·s) | 12.56 | 4.42 | 10.42 | 3.91 | 10.09 | 3.68 |

Soleus force at mid -ift (N/kg) | 14.18 | 5.06 | 12.26 | 4.54 | 11.44 | 4.49 |

**Table 3.**Kinetic and temporal parameters (mean ± SD) from experiment two as a function of each stance-width condition.

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Peak power (W/kg) | 12.63 | 1.87 | 11.18 | 1.48 | 10.96 | 1.85 |

Peak bar velocity (m/s) | 0.94 | 0.07 | 0.87 | 0.08 | 0.84 | 0.07 |

Total squat time (s) | 2.05 | 0.21 | 2.11 | 0.20 | 2.19 | 0.22 |

Ascent duration (s) | 1.02 | 0.09 | 1.06 | 0.11 | 1.10 | 0.10 |

Peak vertical GRF (N/kg) | 11.72 | 1.20 | 11.47 | 1.39 | 11.16 | 1.06 |

Vertical GRF ascent impulse (N/kg·s) | 8.55 | 1.65 | 8.77 | 1.86 | 9.10 | 1.80 |

Medial GRF ascent impulse (N/kg·s) | 0.96 | 0.46 | 1.46 | 0.50 | 2.08 | 0.56 |

Medial GRF descent impulse (N/kg·s) | 0.79 | 0.35 | 1.21 | 0.32 | 1.80 | 0.33 |

GRF vector angle from the horizontal (°) | 88.58 | 3.25 | 85.30 | 3.71 | 82.27 | 3.84 |

Hip energy (%) | 40.44 | 5.26 | 41.87 | 5.66 | 44.15 | 5.68 |

Knee energy (%) | 51.17 | 4.46 | 49.19 | 4.20 | 48.33 | 4.38 |

Anterior knee displacement (%) | 50.42 | 3.41 | 51.26 | 5.83 | 43.41 | 8.13 |

Lateral knee displacement (%) | 26.30 | 11.15 | 23.50 | 10.43 | 18.16 | 11.96 |

Legend: GRF = ground reaction force |

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Hip abduction at mid-lift (°) | −25.03 | 7.99 | −32.52 | 4.64 | −29.28 | 8.35 |

Ankle eversion at mid-lift (°) | −8.12 | 4.41 | −8.77 | 5.85 | −3.70 | 6.75 |

Ankle rotation at mid-lift (°) | −3.50 | 4.60 | −1.06 | 6.47 | 0.95 | 5.02 |

**Table 5.**Muscle forces (mean ± SD) from experiment two as a function of each stance-width condition.

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Peak quadriceps force (N/kg) | 70.60 | 6.46 | 67.48 | 7.53 | 63.99 | 6.75 |

Quadriceps force at mid-lift (N/kg) | 64.38 | 9.06 | 61.71 | 10.37 | 55.68 | 8.58 |

Peak gluteus force (N/kg) | 28.13 | 10.46 | 28.97 | 11.23 | 33.99 | 17.46 |

Gluteus ascent impulse (N/kg·s) | 14.07 | 4.19 | 14.76 | 3.96 | 16.81 | 6.39 |

Gluteus force at mid-lift (N/kg) | 26.05 | 6.65 | 27.68 | 9.01 | 31.98 | 13.68 |

Peak hamstring force (N/kg) | 60.42 | 18.38 | 61.61 | 18.81 | 69.90 | 26.56 |

Hamstring ascent impulse (N/kg·s) | 30.04 | 8.21 | 31.40 | 7.55 | 35.18 | 11.18 |

Hamstring descent impulse (N/kg·s) | 29.89 | 12.64 | 31.17 | 13.05 | 37.21 | 21.40 |

Hamstring force at mid-lift (N/kg) | 56.35 | 11.50 | 59.00 | 14.63 | 66.25 | 20.08 |

Peak gastrocnemius force (N/kg) | 5.78 | 1.04 | 5.90 | 1.16 | 5.25 | 1.23 |

Gastrocnemius force at mid-lift (N/kg) | 4.50 | 1.42 | 4.63 | 1.94 | 3.86 | 1.80 |

Peak soleus force (N/kg) | 12.34 | 2.23 | 12.59 | 2.47 | 11.21 | 2.63 |

Soleus force at mid-lift (N/kg) | 9.62 | 3.02 | 9.89 | 4.13 | 8.23 | 3.85 |

**Table 6.**Three-dimensional kinematics (mean ± SD) from experiment two as a function of each stance-width condition.

NARROW | MID | WIDE | ||||
---|---|---|---|---|---|---|

Mean | SD | Mean | SD | Mean | SD | |

Hip abduction at mid-lift (°) | −20.33 | 8.24 | −20.96 | 8.77 | −23.17 | 9.38 |

Hip internal rotation at mid-lift (°) | 0.21 | 9.52 | 2.85 | 9.18 | 5.70 | 8.86 |

Hip abduction ROM (°) | 13.61 | 7.30 | 11.82 | 6.69 | 9.75 | 7.31 |

Hip internal rotation ROM (°) | 15.09 | 8.71 | 18.29 | 10.13 | 22.52 | 11.45 |

Knee flexion at mid-lift (°) | 134.13 | 4.44 | 132.68 | 5.29 | 128.54 | 6.92 |

Knee flexion ROM (°) | 121.27 | 8.29 | 120.04 | 9.48 | 112.09 | 12.09 |

Ankle dorsiflexion at mid-lift (°) | 27.68 | 6.20 | 25.33 | 7.11 | 19.44 | 6.99 |

Ankle eversion at mid-lift (°) | −7.15 | 7.51 | −8.98 | 6.96 | −12.84 | 2.16 |

Ankle rotation at mid-lift (°) | −3.81 | 3.90 | −6.97 | 4.24 | −10.10 | 6.99 |

Ankle dorsiflexion ROM (°) | 30.54 | 3.10 | 29.93 | 3.76 | 24.66 | 5.11 |

Legend: ROM = range of motion |

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## Share and Cite

**MDPI and ACS Style**

Sinclair, J.; Taylor, P.J.; Jones, B.; Butters, B.; Bentley, I.; Edmundson, C.J.
A Multi-Experiment Investigation of the Effects Stance Width on the Biomechanics of the Barbell Squat. *Sports* **2022**, *10*, 136.
https://doi.org/10.3390/sports10090136

**AMA Style**

Sinclair J, Taylor PJ, Jones B, Butters B, Bentley I, Edmundson CJ.
A Multi-Experiment Investigation of the Effects Stance Width on the Biomechanics of the Barbell Squat. *Sports*. 2022; 10(9):136.
https://doi.org/10.3390/sports10090136

**Chicago/Turabian Style**

Sinclair, Jonathan, Paul John Taylor, Bryan Jones, Bobbie Butters, Ian Bentley, and Christopher James Edmundson.
2022. "A Multi-Experiment Investigation of the Effects Stance Width on the Biomechanics of the Barbell Squat" *Sports* 10, no. 9: 136.
https://doi.org/10.3390/sports10090136