In particular: Soreness and tightness in our forearms can crop up if we spend a lot of time typing. But because the forearm muscles are small and not as heavily involved in everyday activities as most of the postural muscles in the upper back and neck, they all too often get overlooked.
Why does typing on a laptop make our forearms feel tight?
Dave Candy, DPT, a board-certified specialist in orthopedic physical therapy and owner of More 4 Life PT explains that the typing position is not particularly ergonomic, yet it is highly repetitive, which can be exhausting for the small muscles in our forearms, wrists, hands, and fingers.
“Typing uses a sustained, low-level isometric contraction of your wrist extensor muscles to hold your wrist in slight extension while typing,” says Dr. Candy. “Additionally, you use repetitive, low-level contractions from the finger flexors and the finger extensors to strike the keys and then lift your fingers back up off of the keys.”
Without getting too far into the weeds of the physiology of muscle contraction, using your muscles requires energy, and this energy is produced by converting glucose (sugar) in the blood into ATP, which is the energy “currency” for muscles. Oxygen is required to produce this energy. Although there are metabolic pathways that do not rely on oxygen, you are more apt to experience muscle soreness if you are indeed producing ATP without sufficient oxygen (anaerobic metabolism).
“During sustained or repetitive muscle contractions, the pressure from the muscle contraction exceeds the blood pressure of the small blood vessels (capillaries) that supply the little forearm muscles,” says Dr. Candy, who explains that this forces the muscles to use anaerobic metabolism. “Anaerobic glycolysis produces a byproduct that can make your muscles feel sore and stiff. Additionally, anaerobic glycolysis is much less efficient than aerobic metabolism, so your muscles still don’t meet their energy demands.”
Dr. Candy further explains that when there is insufficient energy for the muscles, the muscle fibers actually stay in a partially contracted state because it requires energy to relax the muscle filaments (the contractile proteins in a muscle fiber). This can lead to tension in your muscles and a feeling of tightness.
And it’s not just typing that does this. Dr. Candy says that any low-level, sustained activity that uses the hands can elicit a similar effect in our forearm muscles: writing, playing piano, or gripping a heavy object that we have to carry for a long period of time (like a suitcase) can have the same effect.
Why we should stretch those muscles out
Dr. Candy says that if we don’t take the time to stretch our forearm muscles, we run the risk of developing injuries like tennis elbow and carpal tunnel syndrome.
“Tennis elbow occurs due to overuse of the wrist and finger extensor tendons that attach on the outside of the elbow,” says Dr. Candy.
He explains that carpal tunnel syndrome has more to do with compression of the nerves that run through the carpal tunnel of the wrist than stiffness in the forearm muscles themselves.
“However, the finger flexor tendons also run through the carpal tunnel. Therefore, if the carpal tunnel is already narrowed, repetitive use of the fingers when typing can exacerbate carpal tunnel syndrome symptoms,” says Dr. Candy.
The best forearm stretches to find relief
Fortunately, it doesn’t take much to counteract this. Dr. Candy says that there are a few very simple stretches that can help relieve tightness in our forearm muscles. He walked us through three of them:
1. Wrist extensor stretch
Since the wrist is in a position of slight extension when you type, this means that the wrist extensor muscles can become contracted and tightened, so gently bending your wrist in the opposite direction can help relieve stiffness.
- Sit or stand with your arm out in front of you, elbow straight, and palm facing down.
- Pull your fingers and palm down toward your forearm (the underside where there’s no natural arm hair) using your other hand.
- Twist the forearm so that the fingers point slightly outward (wrist pronation).
- Hold for 30 seconds, relax, then repeat on the other side.
2. Wrist flexor stretch
Stretching the wrist flexors can optimize wrist mobility and prevent carpal tunnel syndrome.
- Sit or stand with your arm out in front of you, elbow straight, and palm facing up.
- Pull your hand down toward the floor using your other hand.
- Hold for 30 seconds, relax, then repeat on the other side.
3. Wrist flexor stretch with your hand on a desk
This is a great stretch for the muscles in the forearm and it will improve wrist and hand mobility if you are feeling stiffness in your wrist from typing.
- Stand with your hand palm down on a desk or firm chair.
- Put your other hand on top of it, over the wrist.
- Rock your body back and forth over your hand in order to stretch your wrist flexors.
- Keep rocking for one minute, relax, the repeat on the other side.
“If you’re typing regularly, perform one set every two hours throughout the workday,” suggests Dr. Candy. “For someone who does a lot of desk work, just doing these couple of stretches several times per day rather than four-plus stretches one to two times per day is probably more beneficial.”
It also helps to pay attention to the ergonomics of your work station. Make sure that your chair is just high enough so that your forearms are as parallel to the floor as possible.
And if you are concerned that your forearm discomfort from typing is getting worse, work with a physical therapist to develop a more robust treatment and prevention plan.
