overview
Physical activity is increasingly recognised as a major factor of health of the general population worldwide. A sedentary lifestyle and overconsumption of processed carbohydrates and other unhealthy foods are considered major culprits of the obesity epidemics.
The American Heart Association recommends getting at least 150 minutes of aerobic exercise per week to strengthen your heart and lungs. Also In 2010 the World Health Organization (WHO) issued guidelines for physical activity. In adults aged 18 to 64 years, aerobic physical activity should be performed throughout the week for around 150 min (moderate intensity) or for 75 min (vigorous intensity), or an equivalent combination of moderate- and vigorous-intensity activity. Bouts of aerobic activity should last around 10 min each. For additional health benefits, adults should aim at doubling the suggested amount of moderate or vigorous physical activity. These guidelines have been adopted in other countries as well.
The AHA published a statement in 2014 that doctors should prescribe exercise to stroke patients since there is strong evidence that physical activity and exercise after stroke can improve cardiovascular fitness, walking ability and upper arm strength.
More recently, a large epidemiological study conducted in more than 55 000 subjects followed for 15 years found that running exerted protective effects against all-cause and cardiovascular mortality even at lower amount or frequency or intensity than recommended by the WHO.
Many different types of exercises can improve strength, endurance, flexibility, and balance. For example, practicing yoga can improve your balance, strength, and flexibility. A lot of lower-body strength-training exercises also will improve your balance.
Among the different types of exercise training, predominantly aerobic activities appear best suited to attain favourable metabolic and cardiovascular effects. Endurance sports are characterised by repeated isotonic contractions of large skeletal muscle groups. Classical examples include running, swimming and cycling among summer sports, and cross-country skiing or speed skating among winter sports.
Endurance training(aerobics) is one of the four types of exercise along with strength, balance and flexibility. Ideally, all four types of exercise would be included in a healthy workout routine. They don’t all need to be done every day, but variety helps keep the body fit and healthy, and makes exercise interesting. To be more precise, endurance contains two categories of itself; cardiovascular endurance and muscular endurance.
(Psychological endurance also plays a key part in success in endurance sport. As such, the ability to compete strongly in endurance events is influenced by our physical fitness and psychological strengths but it cannot be included in a training category)
before going through endurance, let’s clarify some subjects and terms first
Aerobic vs anaerobic
Your respiration and heart rate differ in aerobic activities versus anaerobic ones. glucose is your main energy source during aerobic workout while ATP/PC system and lactic acid energy system are the main source during anaerobic workout.
Aerobic exercise is any type of cardiovascular conditioning or cardio. During cardiovascular conditioning, your breathing and heart rate increase for a sustained period of time. Examples of aerobic exercise include swimming laps, running, or cycling.
Anaerobic exercises involve quick bursts of energy and are performed at maximum effort for a short time. Examples include jumping, sprinting, or heavy weight lifting.
During aerobic exercise, you breathe faster and deeper than when your heart rate is at rest. You’re maximizing the amount of oxygen in the blood. Your heart rate goes up, increasing blood flow to the muscles and back to the lungs.
During anaerobic exercise, your body requires immediate energy. Your body relies on stored energy sources, rather than oxygen, to fuel itself. That includes breaking down glucose.
Aerobic Endurance
During aerobic (with oxygen) work, the body is working at a level that the body’s intake can meet the demands for oxygen and fuel. The only waste products formed are carbon dioxide and water, which are removed by sweating and breathing.
Anaerobic endurance
During anaerobic (without oxygen) work, involving maximum effort, the body is working so hard that the demands for oxygen and fuel exceed the supply rate and the muscles have to rely on the stored reserves of fuel. The muscles, being starved of oxygen, take the body into a state known as oxygen debt and lactic starts to accumulate in the muscles. This point is known as the lactic threshold or anaerobic threshold or the onset of blood lactate accumulation (OBLA). Activity will not be resumed until the lactic acid is removed and the oxygen debt repaid.
Aerobic threshold
The aerobic threshold, the point at which anaerobic energy pathways start to operate, is around 65% of maximum heart rate. This is approximately 40 beats slower than the anaerobic threshold. The aerobic thresholds of untrained males range from 35 to 65% VO2 max.
Anaerobic threshold
The anaerobic threshold, the point at which lactic acid starts to accumulate in the muscles, is considered to be somewhere between 80% and 90% of your maximum heart rate and is approximately 40 beats higher than the aerobic threshold. Your anaerobic threshold can be determined with anaerobic threshold testing.
The primary factor that limits endurance exercise is fatigue. When fatigue reaches a certain point, an athlete’s work rate decreases. The exact point where fatigue limits performance (tolerance level) varies and some athletes can endure much greater levels of fatigue than others.
Is endurance the same as stamina?
When it comes to exercise, the terms “stamina” and “endurance” are essentially interchangeable. However, there are some subtle differences between them.
Endurance refers to your body’s physical capability to sustain an exercise for an extended period. It’s made up of two components: cardiovascular endurance and muscular endurance. Cardiovascular endurance is the ability of your heart and lungs to fuel your body with oxygen. Muscular endurance is the ability of your muscles to work continuously without getting tired.
Stamina is the strength and energy that allow you to sustain physical or mental effort for long periods of time. Increasing your stamina helps you endure discomfort or stress when you’re doing an activity. It also reduces fatigue and exhaustion. Having high stamina allows you to perform your daily activities at a higher level while using less energy. When people talk about stamina, usually they’re referring to their ability to perform an activity without getting tired. It can be thought of as the opposite of fatigue, or the ability to feel energetic for a prolonged period. Having good stamina for a professional basketball player might mean being able to get through an entire game without a dip in performance. Stamina for an 85-year-old grandfather might mean having enough energy to play with his grandkids. Unlike endurance, stamina itself isn’t a component of physical fitness, but it’s the result of becoming fitter.
cardiovascular endurance vs muscular endurance
When a person has excellent muscular endurance, it means that they can perform strength exercises with proper form for an extended length of time without tiring out. muscular endurance takes into account the number of repetitions you complete of one exercise without needing to rest and would include strength training exercises like pushups or weight lifting but Cardiovascular endurance is how efficiently your heart, blood vessels, and lungs to supply oxygen rich blood to working muscles during physical activity (aerobic activity like walking, running, cycling or playing a sport) for a prolonged period of time or for more than 90 seconds.
If you want to increase your muscles’ abilities to work for an extended period, you may wish to train at a low-to-moderate intensity, so that you can keep up with the exercise for 30 minutes or more. Doing bodyweight exercises is a great way to start. As you continue to improve, you can keep increasing the number of reps in your workout, and eventually add weights for even more of a challenge.
If you want to improve your cardiovascular endurance, try slowing down on your next run or bike ride and adding a few more minutes to your total workout time. As you get used to running the new time, you can start to run that time faster, or continue to add more minutes to your endurance training session.
It’s also possible to increase your muscle endurance by doing HIIT (high-intensity interval training). Even though HIIT workouts are usually short yet powerful, they still may enhance your muscles’ capacity to utilize oxygen and in turn improve muscular endurance.
Aerobic training requires the perfect matching of the respiratory and cardiovascular systems, in order to provide the muscles with the necessary supply of energy to be transformed into mechanical work. On the part of the cardiovascular system, increased supply of blood (and oxygen) to the involved skeletal muscles and constant removal of metabolic waste (such as carbon dioxide or lactate) released by the exercising muscles require an increase in cardiac output.
Several factors affect the overall efficiency of the cardiovascular system:
- The capacity of the lungs to inhale large volumes of air (tidal volume) and efficiently absorb oxygen.
- The ability of the heart to pump large amounts of blood (cardiac output) to the working muscles.
- The efficiency of the circulatory system to transport oxygenated blood to the working muscles.
What is strength endurance training?
strength endurance training means training with a high number of repetitions at low weights. Strength endurance training therefore does not train with maximum strength, but only with an intensity of about 50 percent of maximum performance. For strength training it is recommended that the exercises consist of approximately three sets of 20 to 100 repetitions each. A pause of about two minutes must be taken between the individual exercises.
You might see a lot of athletes, like swimmers or tennis players talk about strength endurance training. Basically, It is all about making a little bit of resistance to a aerobic exercise to create both stamina and endurance, but there are a lot of people who disagree on its effects.
What strength endurance promoters believe is that at higher loads, the lactate can accumulate in the muscles and, at too high a concentration, lead to so-called muscle failure, where no further repetitions are simply possible and The muscle does not really fail, but it can no longer provide the necessary amount of energy for movement and If the musculature is over-acidified by enrichment with lactate, it can no longer be repeated due to a lack of energy supply and the removal of harmful substances finally This leads to exhaustion of the energy stores and thus to so-called muscle failure. They say Strength endurance training, however, can improve the musculature’s acid tolerance. This means that acidosis is delayed.
strength endurance advocates highly promote this style of training since they believe Strength endurance training has only a small training effect on maximum strength and muscle mass, but the competitive and professional strength athlete can benefit from the improvement in acid tolerance and the higher capillary density during strength endurance training. It improves not only its performance, but also its ability to recover, because the muscles are better supplied with nutrients. In addition, the lactate threshold is increased and lactate is transported away more effectively. Strength endurance training is also very important for training in the hypertrophy or maximum strength range due to the improved performance and recovery ability.
Although looks convincing and reasonable, Not enough studies have been done on this type of training.
Hypoxemia in endurance athletes
Hypoxemia occurs when levels of oxygen in the blood are lower than normal. If blood oxygen levels are too low, your body may not work properly. Blood carries oxygen to the cells throughout your body to keep them healthy. Hypoxemia can cause mild problems such as headaches and shortness of breath.
Several factors contribute to occurrence of hypoxaemia during exercise: inefficient gas exchange, vocal cord dysfunction, flow limitation in intrathoracic airways and high energy requirements by the respiratory muscles during heavy exercise. This latter effect could be at least partly counteracted by specific training of the respiratory muscles, which was shown to improve exercise performance in both athletes and non-athletes.
Endurance training benefits
Endurance exercise training exerts many positive effects on health, including improved metabolism, reduction of cardiovascular risk, and reduced cardiovascular mortality.
From a physiological point of view, endurance exercise is typically performed at submaximal intensity, with the main purpose of progressively moving the anaerobic threshold, i.e. the beginning of anaerobic metabolism and lactate production, towards higher exercise intensity. This occurs through complex modifications in muscle metabolism, with increased mitochondrial density and oxidative enzymes (i.e. the machinery necessary for energy production), shifts in fibre type, and increased capillarisation of muscle fibres.
Habitual exercise is a potent factor in body weight control at all ages, and also exerts many other positive effects, including prevention of metabolic and cardiovascular disease and promotion of psychological well-being. A recent analysis including studies on the effects of running in sedentary healthy adults confirmed that BMI, body fat, resting heart rate and triglycerides decreased, while maximal oxygen uptake and high-density lipoprotein cholesterol increased, especially when regular training was prolonged over time. Similar results were reported by studies on the effects of endurance training in subjects with the metabolic syndrome
Endurance training downsides
Overall, endurance training is good for health but may become deleterious when performed at high intensity or volume.
elite athletes of both summer and winter sports show increased susceptibility to development of asthma, possibly related to environmental exposures to allergens or poor conditioning of inspired air.
Data obtained in elite endurance athletes are different from those obtained in subjects with low to moderate training volumes. Several reports underline that respiratory symptoms are common in elite endurance athletes, especially of aquatic and winter sports. Asthma treatment is often needed to prevent performance limitation in elite athletes, raising concerns about use of potentially doping substances.
Elite athletes of endurance aquatic sports also show a high prevalence of asthma. The airway pathology shows major similarities between swimmers and asthmatics, with increased production of mucin only found in swimmers. the high concentration of chlorine derivatives in the environment of the swimming pools is a potential risk factor for respiratory problems, and this has raised public health concern for non-competitive swimmers and children attending public pools.
How to help endurance in exercise
Try yoga and meditation. A 2016 study found that medical students who underwent six weeks of yoga and meditation had significant improvements in feelings of peace, focus, and endurance.
prevent dehydration by sipping on water often, especially if you’re working out in hot or humid conditions. If your sessions are particularly long, you may want to consider taking electrolytes to replace minerals lost during sweat.