So, why do we get stiff? Good question. There are actually several causes for muscle and joint stiffness, particularly as we get older. Let's begin by taking a look at what happens to our joints as we get older, as well as other common causal factors, and some ways to prevent stiffness.
As we get older, our muscles naturally decrease in size and strength. This is due in large part to the fact that our tissue begins to be replaced more slowly. In order to function, our bodies are constantly replacing old tissue. Cells stop functioning well, are broken down, and replaced. It is a continuous cycle happening all over our bodies every day. As we age, the replacement of old cells becomes slower, muscles may become weak and tire easily, and we begin to lose muscle mass. Nervous system changes also begin to cause muscles to have less tone and ability to contract, and slower signals begin to effect our reaction times.
Like our muscles, our bones also begin to lose density. They become weaker and more fragile meaning that small falls or bumps are more likely to cause breakage. The loss of bone density as we age is often caused by hormonal changes. As we get older, our bodies produce fewer sex hormones such as estrogen and testosterone, which leads to the loss of minerals in the bones for both men and women. If enough minerals and bone density are lost, it is known as osteoporosis, which literally translated means "porous bones".
In a healthy joint, our bones are meeting with a nice cushion in the middle. This cushion is made up of cartilage, membranes, and fluid. Throughout this space between the bones, we have what is called synovial fluid, which helps to lubricate our joints and make things move more smoothly. As we age, the amount of synovial fluid we produce begins to decrease which makes joint movement harder and often more painful. With less fluid creating lubrication, our bones begin to rub on the cartilage which becomes stiffer due to lack of hydration, and will begin to wear down. Eventually, if all of the cartilage wears down, our bones can begin grinding against each other which can be very painful and make moving difficult. This wearing down of joints is known as osteoarthritis which literally translated means "inflammation of the joint of the bones".
Those of us who experience joint pain and stiffness may notice that it increases with cold weather, or storms. This may seem a little far fetched to some, but it actually has some validity. Many of you may know (or be) someone who can tell a storm is coming because they can "feel it in their bones". Think about how often that person is right. The reason we can feel weather changes in our joints as they wear down is because of barometric pressure. Perhaps you have seen a barometer, which is similar to a thermometer, but instead of telling us the temperature, it tracks pressure in the atmosphere to warn us of changes in the weather. Basically, when you have inflammation or swelling in your joint, a drop in the atmospheric pressure outside your body will allow more swelling to occur because there is less pressure pushing back on you. These dips in pressure often happen before inclement weather, which is how people with arthritis can often tell when a storm will happen later in the day or week.
That explains why we may begin to ache when a storm is approaching, but why does the cold cause us to feel stiff? The affect that cold weather has on our joints is actually pretty much opposite of what happens when the barometric pressure drops. Remember, when the pressure drops, we see more swelling of the joint. What do we do when something is swollen? We put ice on it. Ice, or cold helps to shrink fluid. This means that when the weather gets cold, the already decreased fluid in our joint capsules shrinks further, causing less lubrication, and less cushioning of the joints.
Lack of Use
One of the main causes of joint pain and stiffness is under use. As we move, we are stimulating the production of synovial fluid in our joints. The fluid is also getting worked into the cartilage and softening it. Think about it like oiling a hinge. We put the oil on a hinge, and then we have to move it to work the oil in. As we move the hinge back and forth, the oil has a chance to spread. The same principal can be used for your joints. The more you move them, the more the fluid gets worked through them. If we live a fairly sedentary lifestyle, our joints are not moving enough to get properly lubricated, making movement harder, which means that people move less because it is getting harder, and it becomes a vicious cycle.
Many older people point to a specific incidence where things began to go downhill, usually due to a broken bone. An injury like that, which can leave us unable to move as much for an extended period of time can cause the synovial fluid to be produced in smaller amounts because it isn't being used. Once we start seeing smaller amounts of the fluid produced, it is very difficult for the body to start producing it as the levels we were used to. This is why injuries are so much harder to bounce back from as we get older.
You may notice that you feel more stiff when you first wake up in the morning. This is because your joints have been inactive for several hours. It takes a bit of time and movement to re-lubricate your joints. Many people who notice stiffness upon waking find that it gets easier to move throughout the day.
Many of us have had days where we overused our muscles. Sometimes we hit the gym too hard, take workshops that challenge us to move differently, or try new activities that our bodies are not used to. The next day, you are likely to wake up sore and achy, and you may have difficulty moving due to stiffness. This is an entirely different reason for stiffness than what we discussed with aging. This is stiffness due to what is called an overuse injury or strain. If you are trying to build a workout routine, it is best to build up to a goal, if you suddenly start putting a lot more strain on your body than you are used to, you will just cause strains. Strains need time to recover, and will leave scar tissue. That is one reason why these boot camp style workout classes cause more harm than good, but that is a whole other blog post (which will hopefully be happening soon). Stiffness due to overuse injuries comes from our body working to repair itself. Scar tissue is being laid down, and our fascia (connective tissue) is wrapping around the injured tissue to provide protection and keep the injury from getting worse. Both of these things make movement a little more difficult.
Don't overdo the workout
When creating new workouts or starting new activities, ease yourself into them allowing your muscles to adapt to the new tasks you are asking them to do. This prevents injury and allows for healthy activity. Always make sure to stretch before and after any physical activity, especially those you are not accustomed to.
When it comes to aging, the best thing you can do is to stay active. The more you use your joints, the more synovial fluid will be produced, and the easier it will be to move. The key is to be active throughout your adulthood, and to keep yourself active as you age. If you are noticing joint pain and stiffness due to age, beginning activity where there wasn't much will be much harder because damage has already been caused and often cannot be reversed.
Try low impact activities
Low impact, aerobic activities are a great way to get exercise and prevent stiffness. Try water based exercises like swimming or water aerobics, or low impact movement such as tai chi or yoga which can also help to improve balance and coordination reducing your risk of falls and injury.
Maintain a healthy weight
The more you weigh, the more pressure you are putting on your joints, and the harder it will be to move. Maintaining a healthy weight takes pressure off your joints, allows you to breathe more deeply, increases your stamina, and does much more to increase your ability to move easily. Part of maintaining a healthy weight is proper nutrition. Your body will be able to function more smoothly if you put good, nutrient rich food into it. If you are not confident in making healthy food choices, try talking to a nutritionist to get some good tips on healthy eating.