Using a tablet computer for a long time, especially when typing, is much more likely to cause muscle problems in the user’s upper body than typing on a physical keyboard, a study conducted by the Northern Illinois University cited by the Daily Mail reveals.
These problems are caused by the different nature of the virtual keyboards from the traditional ones – while on a conventional keyboard users can rest their fingers on the keys, but in case of the virtual one they need to keep their hands hovering above the keys to avoid accidental key presses. This can lead to a condition called “prolonged static muscle loading” in the shoulders, when muscles are kept tense and motionless over a longer period of time.
According to Jeong Ho Kim, lead author of the study, this prolonged static muscle loading can lead to musculoscheletal disorders, causing discomfort in the shoulders, and possibly causing “text neck”. This condition was described by a recent study at the New York Spine Surgery & Rehabilitation Medicine as an affliction that affects most people spending extended times texting or chatting on a tablet computer. Holding the head at 60 degrees – a typical position for this activity – causes extra stress in the muscles of the back and the shoulders, possibly leading to “early wear, tear, degeneration and possibly surgeries”.
The study, published in the scientific journal Applied Ergonomics, was conducted with the participation of 19 touch typists with no previous upper body musculoscheletal issues. The participants – currently using virtual keyboards on their smartphones or tablet computers, but with years of computer and laptop use history – were asked to type long passages of Grimm’s Fairy Tales on their virtual keyboards, desktop keyboards and notebooks for five minutes, with electrodes attached to them measuring muscle activity in their forearms and shoulders. The results show that while typing on a virtual keyboard the muscles of the forearms are less active, they were much more used in the trapezius muscles between the neck and the shoulders. These muscles are responsible for supporting the hands above the touchscreen when using a virtual keyboard.
The effects are not severe in the short term, but they accumulate over time, possibly leading to much more serious conditions.
Posted by: Istvan Liptak
To read the original article click here.