Neck brace wearing during sling exercise decreases neck muscle mechanical properties and headache in adults with forward head posture: A randomized controlled trial

Objective: To investigate whether wearing a neck brace during a sling exercise program positively affects craniovertebral angle, mechanical properties of neck muscles, and headache in adults with a forward head posture. Methods: Thirty adults with forward head postures were randomly assigned to an experimental group (sling exercise wearing a neck brace, n = 15) or a control group (sling exercise without a neck brace, n = 15). All participants undertook the sling exercise program (3×/week for 4 weeks). The outcomes were the craniovertebral angle, the mechanical properties of muscles (tone, stiffness, elasticity), and headache. All the outcomes were measured before and after the 4-week training. Results: The experimental group showed a significantly greater magnitude of decreases in mechanical properties of muscle and headache than the control group (frequency of splenius capitis: −3.0 Hz, F (1, 28) = 20.733, p < 0.001, ƞ 2 = 0.425; stiffness of splenius capitis: −67.4 N/m, F (1, 28) = 9.999, p = 0.004, ƞ 2 = 0.263; decrement of splenius capitis: −0.1 d, F (1, 28) = 6.188, p = 0.019, ƞ 2 = 0.181; frequency of upper trapezius: −2.8 Hz, F (1, 28) = 8.718, p = 0.006, ƞ 2 = 0.237; decrement of upper trapezius: −0.2 d, F (1, 28) = 5.194, p = 0.030, ƞ 2 = 0.156; frequency of sternocleidomastoid: −2.7 Hz, F (1, 28) = 8.561, p = 0.007, ƞ 2 = 0.234; stiffness of sternocleidomastoid: −112.8 N/m, F (1, 28) = 13.586, p = 0.001, ƞ 2 = 0.327; headache: −4.7 points, F (1, 28) = 7.221, p = 0.012, ƞ 2 = 0.205, respectively). Conclusions: Wearing a neck brace while performing sling exercises might provide an effective means of relaxing neck muscles and reducing headaches in adults with forward head posture.