What exactly makes endurance possible is a question that must be answered because it is such an important part of athletic performance.  The answer is in understanding the intricate interactions that take place between the many physiological and biochemical components.

Most internet strength based coaches don't understand these, and so it is no surprise that most of the fitness information consumers do not either. In this article, we will explore the science behind endurance and provide you with some actionable recommendations on how to improve your own personal endurance.

Acquiring Knowledge about Endurance Physiology

Endurance is defined as the capacity to participate in physically taxing activities for extended periods of time without experiencing exhaustion from such activities. This is made possible by the coordination of a number of different physiological systems, including the neurological, muscular, respiratory, and circulatory systems.

While the respiratory system is responsible for regulating the levels of oxygen and carbon dioxide in the body, the cardiovascular system is in charge of supplying the working muscles with oxygen via blood as well as the nutrients contained within it. While the nervous system is responsible for coordinating and controlling the activity of the muscles, the muscular system is the one responsible for producing force and power.

During all exercise, these several systems work together to provide the energy that is necessary for continuing to be physically active. After a period of time, the body is able to adapt to the stresses that are imposed by endurance training, which results in longer and more intense performances.

Aerobic Metabolism

One of the most important aspects of stamina is aerobic metabolism, which may be defined as the body's ability to convert oxygen into usable fuel using fat as an energy source. The anaerobic metabolic process is less efficient than the aerobic metabolic process and relies on carbohydrates that are already stored in the body. The key components to remember here for these two terms is that aerobic simply means "with oxygen", and anaerobic means " without oxygen". It is possible to improve one's endurance performance and delay the onset of weariness by increasing their body's capacity to use oxygen more efficiently.

To boost your aerobic metabolism, you should incorporate into your routine a range of endurance exercises. The cellular powerhouses that are responsible for driving aerobic metabolism are termed mitochondria, and as a result of low-intensity exercise, both their number and size increase. Exercise performed at a low to moderate level improves cardiovascular function and increases the capacity of the respiratory and circulatory systems in the body. 

The aerobic system is easily the most important energy system in the body. While responsible for long endurance efforts like a trail run, it is also responsible for any activity that lasts more than about 75 seconds. The longer the event, the greater the aerobic demand. Even a sport seemingly very intense, like MMA, with a 15 minute match length, will have a significant aerobic demand. 

The best way to train the aerobic system is using a format we typically associate with endurance. That is, running, rowing, cycling, swimming, stair master, versaclimber, or elliptical. This is not best suited to circuit style, loaded training. 

The part played in endurance by anaerobic metabolism

Anaerobic metabolism is still necessary for endurance, despite the fact that aerobic metabolism plays the most important part in the process. Anaerobic metabolism is defined as any metabolic process that does not require the presence of oxygen in order to produce energy. When the body requires more energy than is being provided by oxygen during high-intensity activity, anaerobic metabolism begins to function. 

Increasing anaerobic metabolism can boost endurance performance, bit it comes at a cost. This is accomplished by delaying the onset of weariness and making it possible to engage in more strenuous activities. If you want to boost your anaerobic metabolism, you should incorporate high-intensity interval training (HIIT) into your workout routine along with strength training.

High-intensity interval training (HIIT) is a form of cardiovascular exercise that consists of brief periods of extremely strenuous activity followed by periods of relaxation. Performance in endurance events and the body's capacity to produce energy in the absence of oxygen are both improved by this type of training. 

The best way to train the anaerobic system is using the same type of training as your aerobic work. That is, running, rowing, cycling, swimming, stair master, versaclimber, or elliptical. This is not best suited to circuit style, loaded training. 

On the other hand, lifting weights improves the body's ability to store carbohydrates and utilise them for energy, so improving the anaerobic metabolism. Resistance exercise can improve endurance performance in addition to being favourable to cardiovascular health.

In both cases, the debt that needs to be repaid is obvious. Despite having engaged in a short burst of activity, you will find yourself panting for breath after completing even a short interval, or a set of strength work. That panting is the oxygen debt. You worked without oxygen and provided energy in the absence of oxygen (because your demand was too high for oxygen to be the main source) and now you must repay the loss of energy with your aerobic system. Oxygen debt - your recovery between efforts - is powered by your aerobic system. 

Strengthening the muscle's resistance to fatigue

In addition to improving aerobic metabolism, there are a number of other strategies available for enhancing muscle endurance. This is called strength endurance. These include the following:

• By increasing the size and density of muscle fibres, as well as the amount of oxygen that is delivered to muscles, one may both store and produce more energy from their muscles.

• One effective strategy for achieving these objectives is to engage in resistance training, which helps to improve both the size and density of muscle fibres as well as the amount of energy produced by the muscles. In addition to boosting cardiovascular health, resistance training also increases one's ability to sustain activity for longer periods of time.

As opposed to aerobic and anaerobic work, this is best suited to circuit style training allowing you to target muscle actions and movements effectively to overload the patterns and force adaptation in those ranges. A good example for someone looking to improve hill running performance would be the Leg Blaster: 

• 10/ 10 alternating jump lunges

• 10 jump squats

• 10/ 10 alternating lunges

• 10 squats

• 10 burpees

This circuit will train multiple movement patterns of the lower body while simultaneously training power, power endurance, and strength endurance. 

Determining Training Methods

When it comes to figuring out which style of training to use for ultimate performance you will need a combination of aerobic work, anaerobic work, and strength endurance. The easiest way is simply to design your week around a solid base of aerobic work, and then sprinkle in at most one session of each per week. For example, this potential week for a runner getting ready for a hilly half marathon: 

• Monday - Off

• Tuesday - Easy run 30mins, lower body strength + core

• Wednesday - Easy run 60mins

• Thursday - Off

• Friday - Leg blaster workout, 4 rounds, then 4 x 500m above race pace hill run with easy jog back recovery on 3-4% gradient

• Saturday - Long run 90mins, with final 15mins at race pace

• Sunday - Easy run 30mins

If you want to be a bit more specific about how you add in the extra work, you need to understand where it is you're lacking. Many just always assume their deficiency is in strength, as that is what is most talked about in online fitness. Maybe you lack strength, but maybe it's something else. How would you know? 

Let's take one example of the runner above. If they can't maintain a steady pace throughout the race they lack the aerobic ability and need more base training. If they can maintain the same steady pace seemingly forever but have no speed (for example, their 5k time is exactly half of their 10k time) then they need some anaerobic work. If they have some speed but seem to fall behind going up hills they need strength. Now simply add in the elements missing into your training plan. 

In example two, let's use a typical middle aged blue belt doing BJJ. If he can't manage to train all the way through a class without needing a break, then he lacks the base aerobic fitness and needs more steady state, low intensity work. If he can train through the whole class without needing a break but finds he runs out of steam within a round or two he needs more anaerobic work to better learn how to buffer lactic acid and be able to put out at high intensities repeatedly. If he finds he gets pushed around easily, then he needs more strength. And if he is fine in early rounds, but finds in later rounds he starts to get pushed around, then he needs more strength endurance. 

Conclusion

Training as you get older can no longer be as easy as "just do something". If you want to get the best results you can while avoiding injury and burn out you need to be far smarter about your training plan. If you don't have a plan that is going to be a problem as you'll find yourself stalling or frequently being hurt, and ultimately quitting due to frustration. Spend some time using the yearly planning idea as well as this post to create a sound plan for yourself.