Introduction:
The push-up exercise is a common therapeutic and fitness exercise for improving shoulder function and treating shoulder pathology that can be performed with many variants.
To date, previous studies have focused on upper body muscle activations, whereas a lack of literature exists regarding shoulder and elbow joint kinematics during push-up variants. Since the palm rotation gets its maximum degree of freedom from the shoulder complex and elbow. Therefore, the aim of the current study was to evaluate the effect of palm rotation on the shoulder and elbow joint kinematics during push-up.
Research Question:
What is the effect of the palm rotation on kinematics of shoulder and elbow during push-up exercise?
Methods:
Fifteen fitness athletics (weight: 68.35±7.18 kg, height: 175±3.40 cm, age: 24.50±7.5 years, and experience: 12±3 years) executed push-up in three angles of palm rotation on the ground: external (180°), internal (0°), and medium (90°). Participants performed a set of 5 repetitions for each push-up variant. Ten Vicon motion captures (Vicon MX, Oxford, UK, 200 Hz) were used to record the surface marker trajectories attached to bony land markers. The Wu shoulder model consists of 5 segments, and 10 degrees of freedom was used as a base model in the OpenSim to estimate kinematics. The generic model was scaled by mass, height, isometric strength, and markers data in the static position. The inverse kinematics was used to estimate elbow and shoulder joint kinematics. Matlab was used for data normalization and statistical analysis.
4. Results:
Presents Range of Motion(ROM) and kinematic results for three angles of palm rotation on the ground: external, internal, and medium during pushup. Significant differences were observed among three rotation of palm positions (p < 0.05). The largest differences were observed at the beginning and terminal phases of the push-up movements.
5. Discussion and conclusion:
The push-up is a popular exercise for enhancing shoulder stability, strength, and control. The main aim of the current study was to find the relationships of joint kinematics among the rotational positions of palms. According to results, utilization of push-up exercise without kinematics adjustment on in rehabilitation should be considered cautiously. In addition, trainers and physical therapists should be aware of elbow and shoulder joint kinematics when prescribing and monitoring exercise progression. Therefore, we suggest both trainers and physical therapists consider the kinematics variables before the prescriptions of push-up.