Treadmill Fatigue Fighters

By Rick Morris

Wouldn’t it be nice if you could run forever and never get tired? Just imagine being able to run at your top speed without ever feeling the effects of fatigue. That would be an ideal world for runners – or would it? If you really think about it you need fatigue. Without the effects of fatigue there would be no challenge to running. There would be no purpose for your training runs. There would be no reason to run! That’s something you will never need to worry about. Fatigue is an unavoidable part of running. In a sense, running is like a contest pitting your physical strength and spiritual will against the multi faceted attacks of fatigue. Your daily training runs will strengthen your body and improve its ability to fight off and deal with fatigue. Fatigue can take many forms. The type of fatigue that affects you depends upon how fast and how far you’re running.

Phosphocreatine Depletion

A sprinter must deal with depletion of phosphocreatine, the source of short term, high intensity energy. This system produces energy for short, intense bursts. Your supply of phosphocreatine will be depleted within 5 to 20 seconds of intense activity. This is the primary cause of fatigue when performing an all out sprint but is of little concern to a distance runner. A distance runner may use this system when sprinting to the finish line or when you accelerate to pass a competitor, but the fatigue caused by this system should really not concern you during most of your runs.

Blood Acidity

When you are running at race pace for distances from 800 meters to 10 kilometers another type of fatigue rears its ugly head. It is commonly believed that that lactic acid, a by product of energy production, is the cause of muscle fatigue when running at these paces. Now we know that not only does lactic acid not cause fatigue, but it is a valuable source of energy production.

Lactic acid accumulation may indirectly contribute to fatigue at fast paces. As you increase your pace, lactic acid begins to pile up faster than your body can process it for energy. The accumulating lactic acid goes through a conversion that results in a build up of hydrogen ions. The hydrogen ions cause a condition called acidosis. This condition causes your body to release buffers that reduce the effect of the hydrogen ions. The end result is that the buffers cause a decrease in the muscle pH, which causes a decrease in the ability of your muscles to do work.

Some exercise physiologists believe that this process is caused by your body trying to protect itself. If the acids in your muscle were allowed to continue to rise, serious muscle damage could be the result. The buffers that decrease your muscles ability to work could be a self protective mechanism that keeps you from damaging your body by continuing to run at an intense pace when your muscles are already too acidic.

Potassium Buildup Fatigue

A recent and interesting finding is that a buildup in potassium can also be a major contributor to running fatigue. Your muscles depend upon an exchange between potassium and sodium to fire a muscle contraction. During high intensity distance running, potassium is released faster than it can be used. This can cause an interruption or weakening of the ability of your muscles to contract - or in simpler terms, it causes fatigue. This potassium build up takes place at roughly the same pace and at the same time as the hydrogen ion build up, so it is difficult to determine whether the hydrogen ion build up or the potassium is causing the fatigue. The most recent research seems to point to potassium build up, but both probably play a role.

Hypoglycemia

Phosphocreatine build up, blood acidity and potassium accumulation are all causes of fatigue when running near or faster than 10K race pace, but are not usually a problem during more moderate paced running. Paces less than 10K race pace are normally slow enough that your body is able to clear the accumulating lactic acid and potassium. The more moderate running paces bring their own types of fatigue that you must do battle with. The first and most common face of moderate pace, long distance running fatigue is hypoglycemia, which is more commonly known as carbohydrate or glycogen depletion. When you hear the term “running into the wall”, most runners are referring to hypoglycemia.

When you eat foods containing carbohydrates, your digestive system converts the various sugars in the carbohydrates into glucose. This conversion is necessary to make the carbohydrates usable by your body. When the glucose is released into your bloodstream a hormone called insulin is also released. Insulin tells your body’s tissues to store some of the newly released glucose. This is stored in your muscle and liver as glycogen.

Glycogen depletion is one of the main causes of fatigue for marathon runners. During marathon pace runs, your stores of glycogen will be depleted at around 18 to 21 miles (29 to 35 km). This point is referred to, by marathoners, as “hitting the wall”. Much of this sensation is caused by a nearly complete depletion of glycogen.

Central Nervous System Fatigue

Your brain is a remarkable organ. It toils endlessly in directing all of the physical, mental and emotional processes needed to keep your body running efficiently. As much work as the brain does on a daily basis, it has been estimated that most of us only use about 10% of our brains total capacity. That leaves a lot of power that is going untapped. As a runner your brain may be performing a service that you are not even aware of.

One of the most recent theories concerning the causes of running fatigue involves your brain and your central nervous system (CNS). Your brain controls every action that takes place in your body, both conscious and sub-conscious. It controls your breathing, your heart rate and is responsible for sending signals to your muscles to contract. It is now believed that your brain may be a major if not the primary cause of running fatigue in not only the marathon but also shorter running events.

Your brain and your spirit are sometimes at odds. Your brain wants to keep your body in a state of balance. It wants to maintain your acidity levels and your stores of glucose. It wants to protect your muscles and organs from damage. Your spirit is more concerned with successfully completing your goal. One of these times is during running events. Your spirit wants to run faster and further than your brain considers to be safe. When you run long distances your body begins to run low in energy providing glycogen. Your muscles also begin to suffer some minor damage and trauma from the repeated strides and contractions. According to this latest theory your brain takes over at that point. In effect, your brain tries to over-ride your spirit. Since you won’t consciously stop running or slow your pace, your brain begins to decrease the signals to your working muscles. You feel this in the form of fatigue and pain. It becomes much more difficult to maintain your pace.

While this theory is relatively new and unproven, it does explain why many athletes are able to increase their pace during the final miles of a marathon. If the cause of the fatigue were purely physical, increasing pace at that point should be impossible. One of the benefits of training may be that your brain begins to learn and understand that your muscles are able to withstand longer and longer distances or faster paces. As a result you are able to run longer and faster before your brain steps in to slow you down.

Treadmill Fatigue Fighters

It’s true that fatigue is an unavoidable and necessary part of running, but that doesn’t mean that you shouldn’t do some training to reduce the impact of fatigue. Where is the best place to do your fatigue fighting workouts? You guessed it – your treadmill! There are many great benefits to running on the treadmill. One of the most beneficial is the unrelenting pace of the treadmill belt. When you do hard training on the track or road you tend to sub consciously slow down when you become fatigued. You may not intend to slow your pace, but you brain and body sometimes insists that you do. When you do the same training on your treadmill you are forced to maintain your planned pace throughout your workout. Your only choices are maintain your pace or fall of the treadmill! Being forced to maintain your planned pace throughout your training run makes treadmill training the superior choice. Here are two fatigue fighting treadmill workouts that will elevate your fitness and your ability to fight off both the physical and mental aspect of fatigue.

One Minute Repeats

This is a great workout for fighting the effects of blood acidity and potassium accumulation. It also does a good job of mental training. This is a simple but physically challenging workout that should be done once every two weeks.

Elevate your treadmill to 1 percent and warm up with 5 to 10 minutes of easy running. Now run for one minute at very close to your fastest pace. This pace should feel very hard. After one minute at that pace, slow your treadmill to an easy pace and jog for 2 minutes. Keep repeating that sequence of one minute at nearly full pace and two minutes at an easy pace for your desired number of repetitions. You should take no rest between the repeats. Keep going until you cannot hold a strong pace on your hard one minute repeats. Then cool down with 10 minutes of easy running.

800/400 Meter Compound Sets

This is a classic track workout that works very well on your treadmill. Elevate your treadmill to 1 percent and warm up with 10 minutes of easy running. After your warm up, run for 800 meters or ½ mile at a hard pace. If you complete in local 5K races you should be right at your 5K race pace. If you don’t know your 5K pace, simply run at a pace that feels hard. Then without any rest or recovery speed up to your fastest pace for 400 meters or ¼ mile. Recover with 4 minutes of complete rest before repeating this for your desired number of repetitions. Start with 3 repetitions for your first workout and gradually build up to 6 repetitions.

Running Planet

Promote Your Page Too