The two exceptions were the FDI and RTRAP muscles. While seated the median muscle activity levels in the APB averaged 5.2 ± 0.6%MVE, 8.0 ± 0.9%MVE in the APL, 5.2 ± 0.6%MVE in the FDI, 5.6 ± 0.6%MVE in the ED and 2.8 ± 1.1% and 4.3 ± 1.5%RVE in LTRAP and RTRAP respectively. Sitting and standing influenced trapezius muscle activity. When entering an SMS message while standing, LTRAP and RTRAP 10th, 50th and 90th percentile muscle activity was significantly higher compared to performing the same task sitting. Finally, when comparing muscle activity when subjects entered SMS messages on their own and the standard phone while sitting, only small differences were observed in FDI muscle activity. When subjects used their own phone, both median (p = 0.052) and peak 90th percentile muscle activity was higher.