Mean ± standard deviation muscle activity and muscle activity ratio during concentric, isometric, and eccentric contraction, with and without biofeedback
Variable | Muscle contraction | Without biofeedback | With biofeedback | Mean difference (95% CI) | p-value |
---|---|---|---|---|---|
Infraspinatus (%MVIC) | Concentric | 20.39 ± 5.65 | 28.86 ± 4.46 | 3.04 (0.45–5.63) | 0.025 |
Isometric | 28.15 ± 10.76 | 36.94 ± 11.86 | 1.71 (0.44–3.86) | 0.001 | |
Eccentric | 15.87 ± 4.51 | 18.20 ± 4.89 | 3.13 (0.74–5.51) | 0.014 | |
Posterior deltoid (%MVIC) | Concentric | 11.29 ± 6.60 | 7.97 ± 4.81 | 3.31 (1.41–5.21) | 0.002 |
Isometric | 8.24 ± 3.42 | 6.01 ± 2.26 | 2.23 (0.93–3.53) | 0.002 | |
Eccentric | 10.19 ± 4.19 | 9.10 ± 3.57 | 1.08 (0.05–2.11) | 0.040 | |
Activity ratio | Concentric | 2.38 ± 1.30 | 4.68 ± 2.47 | –2.30 (–3.51 to –1.09) | 0.002 |
Isometric | 3.81 ± 1.72 | 6.50 ± 2.02 | –2.69 (–4.03 to –1.33) | 0.002 | |
Eccentric | 1.83 ± 1.11 | 2.23 ± 1.00 | –0.39 (–0.85 to 0.06) | 0.080 |
Values are presented as mean ± standard deviation. %MVIC, percentage of maximal voluntary isometric contraction; CI, confidence interval.