Rachel Hector1, Jody L Jensen2. 1. Department of Kinesiology & Health Education, University of Texas at Austin, 2109 San Jacinto Blvd D3700, UT Mail Code: D3700, Austin, TX 78712-1415, USA. Electronic address: rachelhector@utexas.edu. 2. Department of Kinesiology & Health Education, University of Texas at Austin, 2109 San Jacinto Blvd D3700, UT Mail Code: D3700, Austin, TX 78712-1415, USA. Electronic address: jljensen@austin.utexas.edu.
Abstract
BACKGROUND: This study examined the weight-bearing responsibility of the head and neck at moments of peak force during three headstand techniques. METHODS: Three matched groups of 15 each (18-60 years old) were formed based upon lower limb entry/exit technique: symmetrical extended, symmetrical flexed, and asymmetrical flexed. All 45 practitioners performed 3 headstands. Kinematics and kinetics were analyzed to locate peak forces acting on the head, loading rate, center of pressure (COP) and cervical alignment. FINDINGS: During entry, symmetrical extended leg position trended towards the lowest loads as compared to asymmetrical or symmetrical flexed legs (Cohen's d = 0.53 and 0.39 respectively). Also, symmetrical extended condition produced slower loading rates and more neutral cervical conditions during loading. INTERPRETATION: Subjects loaded the head with maximums of 40-48% of total body weight. The data support the conclusion that entering the posture with straight legs together may reduce the load and the rate of change of that load.
BACKGROUND: This study examined the weight-bearing responsibility of the head and neck at moments of peak force during three headstand techniques. METHODS: Three matched groups of 15 each (18-60 years old) were formed based upon lower limb entry/exit technique: symmetrical extended, symmetrical flexed, and asymmetrical flexed. All 45 practitioners performed 3 headstands. Kinematics and kinetics were analyzed to locate peak forces acting on the head, loading rate, center of pressure (COP) and cervical alignment. FINDINGS: During entry, symmetrical extended leg position trended towards the lowest loads as compared to asymmetrical or symmetrical flexed legs (Cohen's d = 0.53 and 0.39 respectively). Also, symmetrical extended condition produced slower loading rates and more neutral cervical conditions during loading. INTERPRETATION: Subjects loaded the head with maximums of 40-48% of total body weight. The data support the conclusion that entering the posture with straight legs together may reduce the load and the rate of change of that load.
Authors: Varun Malhotra; Avinash E Thakare; Sandip M Hulke; Santosh L Wakode; Rachna Parashar; Naveen Ravi Journal: J Family Med Prim Care Date: 2021-01-30