Why Do You Get Swollen Hands When Hiking?

There is no doubt that hiking is a physical activity, and like all physical activities, it can have varying effects on your body. From blisters on your feet to sore muscles, hiking can bring with it myriad ailments. One thing beginners wonder is why you get swollen hands when hiking.

The main reason you get swollen hands when hiking is due to increased centrifugal force. Centrifugal force increases when you swing your arms during hiking, causing fluids to be “pushed” into and remain in the hands, leading to swelling.

Other theories for swollen hands when hiking include impaired blood flow or congested lymph drainage from tight backpack straps, and impaired electrolyte imbalance. Below, we’ll go through each of these theories to truly understand why your hands swell when you’re hiking.

Impaired Blood Flow/Congested Lymph Drainage

Oftentimes new backpackers use a backpack incorrectly. They tighten the shoulder and chest straps too tight, thereby carrying too much weight on their shoulders. But does this cause the hands to swell? First, we need to understand what causes swelling at the physiological level. Swelling is when fluid enters your fingers and stays there, leaving them “puffed up.”

Blood Vessels

Blood vessels are part of the circulatory system that begins with the heart. Our heart pumps blood out into the arms by the way of arteries. Once the blood reaches its destination, in our case it’s the fingers, the oxygen from the blood is given to the cells and then the deoxygenated blood returns to the heart for a new shipment of oxygen. It is transported back to the heart by way of the veins.

When this transport system gets hung up, swelling may occur. Say, for example, you are hiking and you tighten your straps down too much on your shoulders. This impedes the blood from either getting to your fingers or returning to the heart.

Blood Vessel Compression

But does compression on the blood vessels cause your fingers to swell? It’s unlikely to be the case. This compression at the shoulders acts on the arteries’ and the veins’ blood flow. It is as if you have put a tourniquet on and prevented fluid from passing efficiently in both directions.

First, the area will experience ischemia or lack of blood flow. The hands and fingers may blanch (turn white) or become light blue, meaning they are not getting enough oxygen. Also, they may feel tight, but not necessarily swollen. The longer the compression, the more painful this becomes.

Nerves

The nerves from the shoulder area also become compressed. This leads to tingling and eventual numbness in the hands and fingers. This is like when your foot falls asleep after sitting on it for too long. This does not lead to swelling, but just an uncomfortable feeling in your hands.

The Lymphatic System

The lymphatic system works a little differently. The lymph system contains a couple of organs (spleen and thymus) and a network of lymph glands and lymph nodes placed strategically throughout the body.

The purpose of the lymphatic system is to rid the body of toxins, waste, and other unwanted materials. When there is blockage of the lymphatic system a couple of things happen. A blockage prevents fluids from draining (removing the toxins) and the buildup of swelling leads to what is known as lymphedema.

Lymphedema is often found in people who have had radiation treatment for breast cancer or certain surgeries in the upper arm. It is due to damage of the lymph nodes and lymph glands in the upper arm. If this is you, then you may already experience lymphedema that worsens when out hiking. This is therefore not the cause of regular hand swelling when hiking and is a specialized case.

Hyponatremia And Electrolyte Imbalance

A couple of things happen when we hydrate with only water during hiking. First, we prevent or delay dehydration, which is a good thing. Second, we upset the electrolyte balance, primarily that of sodium. This can be dangerous or even fatal.

To remain in balance (hydration-wise), we need to balance both water and electrolytes. However, when you only drink water, you don’t get the required sodium to keep the system in balance. Excess water versus your electrolytes is known as Hyponatremia, which means there is not enough sodium in the fluid.

Symptoms Of Hyponatremia

Hyponatremia symptoms include headaches, nausea, vomiting, loss of energy, restlessness, muscle spasms/weakness/cramps, seizures, and comas. They do not, however, include hand swelling, so this is not the reason either.

Centrifugal Force From Swinging Your Arms

When we walk, hike, and run, we rely on swinging our arms to keep our balance and maintain forward motion. But swinging the arms has a potentially detrimental effect on fluid dynamics in the arms.

A swinging motion, which is a portion or arc of a full circle of motion going back and forth, increases the centripetal force up toward the shoulder. Also, the normal force causes fluids to push outward toward the finger, in a similar way to how you might find yourself being pushed into the right side of a car as it goes round a left-hand corner. This outward force is called centrifugal force.

Centrifuges

Another way to think of it is like a centrifuge. A centrifuge is a device that is used to apply centrifugal force to liquids of different densities. In a lab, the denser liquids will be pushed away from the opening of the test tube and the less dense liquids stay closer to the opening.

When we walk and swing our arms we act like a centrifuge. This action is of course much slower than that of a centrifuge, giving us the understanding that this is a slow process. This is why your fingers don’t swell immediately on your hike, but maybe after 3 to 5 miles.

Fluids inside our cells get ‘pushed’ out and remain in our fingers. This happens outside of what is happening in the circulatory system (arteries and veins). The blood continues to flow and provides for oxygen to reach the cells while carbon dioxide is removed from the cells as the blood heads back to the heart. However, it’s this fluid remaining in the fingers that causes hand swelling on a hike.

Other Factors That Play A Role In Hand Swelling

Altitude

Exposure to high altitude can cause swelling to occur in the arms, face, and legs. This is caused by pulmonary edema and often occurs without any other symptoms. Pulmonary edema occurs as a result of big pressure differences outside and inside the lungs. Water begins to pool inside the lungs, and it becomes challenging to breathe. This is a very dangerous condition.

While pulmonary edema can cause hands to swell, this is a different situation than that which we are describing with everyday hand swelling. If you experience symptoms of pulmonary edema, seek medical attention immediately.

Humidity

Humid days, especially in the summer, can cause increased hand swelling. A hot day will cause increased blood flow to the hands, and they begin to heat up faster. Normally when this happens our hands sweat, and the sweat evaporates, helping to cool us down.

Unfortunately, on particularly humid days, our body is less able to evaporate the heat from our skin and this causes a backup of fluid. Fluid from beneath the skin is unable to escape and causes the hands and fingers to swell. Couple a hot and humid day with swinging your arms on a hike and you have increased hand swelling.

Cardiovascular Activity

Exercising causes hands to heat up by the opening up of blood vessels. This leads to increased blood flow and therefore a chance of increased swelling. This increased level of activity, paired with the arm swinging motion, causes swelling in the hands when hiking.

Salty Foods

Eating salty foods may cause your hands to swell. After eating a salty meal, our cells attract water into them to balance the salt to water ratio, causing slight swelling. Some medications for treating arthritis also cause water to be held in the cells and become swollen.

Cold Weather

When it’s cold outside, blood vessels constrict, causing the hands to shed fluid. However, quickly warming the hands may cause the hands to bring in excess fluid (warm blood) and cause the hands to swell.

How Do I Prevent My Hands From Swelling During A Hike?

Raise Your Hands

Raise your hands above your head and pump your hands into fists. This will allow gravity to assist in reducing the swelling in your hands, by drawing fluid back up the arms. This also allows your muscles to help squeeze out the swelling. It may take some time, but you should notice a big difference in about five minutes. Note that this may affect your balance, so don’t do it on tricky sections!

Bend Your Elbows

Bend your elbows so that your hand is higher than your elbows. Like the previous tip, this allows our bodies to reduce swelling using gravity.

Try Hiking Poles

Hiking poles do a couple of things. They cause your hands to use muscles which act as pumps to pump out fluid. But they also cause you to bend your elbows and keep hands near or above your elbows, limiting the effects of any centrifugal force.

Take A Break

When you stop hiking you stop swinging your arms. This stops the centrifugal force, and allows fluid to drain back out of your hands.

Hiking With Raynaud’s Disease

If hiking weren’t hard enough as is, people with Raynaud’s Disease have to take more caution when they hike. Raynaud’s is a rare blood vessel disorder primarily affecting the fingers and the toes. Sufferers’ blood vessels narrow when they are cold or feeling stressed, meaning blood can’t get to the surface of the skin. This can leave your skin looking blue or white.

Tips For Hiking With Raynaud’s Disease

First, keep your hands warm with gloves while hiking in colder weather. Second, exercise regularly to improve your circulation. Many new backpackers just start hiking or going on longer and longer walks, which is not the right way to go. However, the more frequently you perform cardiovascular exercise off the trail, the more prepared you will be in the mountains.

Inflammation can reduce the body’s ability to get circulation to the hands and fingers. Foods such as highly processed carbohydrates can cause increased inflammation. Reducing or eliminating these foods helps to increase circulation.

Hiking While Pregnant – Hand Swelling

During pregnancy, the body produces more blood and bodily fluids to meet the developing baby’s needs. Because of this increase in fluid, swelling is normal at any time. A pregnant woman may therefore experience more hand swelling than normal when hiking, and it will occur much earlier too.

Preeclampsia

Sudden swelling in the hands and feet during a hike or at any other time during pregnancy may be a sign of preeclampsia. Pre-eclampsia is a complication that may happen after about week 20. It is a serious sign that something is wrong. Symptoms include damage to the organs, high blood pressure, and swelling in the hands and feet. It is best to seek medical attention immediately.

Hiking With Lymphedema

Lymphedema usually occurs after special types of shoulder surgery or post-mastectomy and radiation treatment. Lymphedema is damage to the lymph glands and nodes in the upper arm. Hiking with lymphedema can be a challenge. But there are some ways to help manage increased swelling during your backpacking trip if you have Lymphedema:

  1. Wear a compression garment – This keeps constant mild pressure on the arm and prevents the arm and hand from swelling
  2. Use a hiking pole – This keeps the hand and arm supported, the elbow bent, and the hand above the elbow, reducing the chance of increased swelling
  3. Avoid too much lifting with the affected arm
  4. Elevate your arm
  5. Hike in cooler weather – The increased temperature can get very uncomfortable when wearing a compression sleeve, and warmer, more humid weather can cause increased swelling in the hand and arm

Final Thoughts

You get swollen hands when hiking as a result of the centrifugal force experienced as you swing your arms. This causes fluid to build up in the hands, leading to swelling. Other factors, like humid weather and certain medical conditions, may also contribute to hand swelling when hiking.