Good Cycle Ergometry Literature Review Example

INTRODUCTION

Cycle ergometer is a stationary bicycle attached with an ergometer which measures the work done by the person who is exercising (Wikipedia, 2015). In order to determine the cardiopulmonary health it is important to evaluate the exercise tolerance by an individual. In this paper we will discuss about the factors affecting the cycling economy and efficiency. We will look into the literature on this topic and closely analyze the facts that will be coming out of those researches. We will also discuss the implications of altered economy and efficiency in depth.

FACTORS AFFECTING CYCLING ECONOMY

Some of the factors that affect the cycling economy are: anaerobic threshold of the cyclist, muscle fiber type, muscle myoglobin concentration, muscle capillary density, anthropometric dimensions of the cyclist and aerodynamics or air retardation. Lets discuss some of these in details (Faria, 1992):
MAXIMAL STRENGTH TRAINING: Sunde et al., did a research study over the subject in which they wanted to show that maximal strength training improves cycling economy. They took a sample of sixteen cyclists who were divided randomly into two groups. One of the groups was the intervention group and the other was control group. Out of them, twelve were men and four were women. Thirteen of them were able to complete the study, ten men and three women. The group of intervention consisting of seven men and one woman did half squats, four sets of four repetitions, three times in a week, for a period of eight weeks. While the group of control continued with their normal training of endurance. The results showed significant improvements in terms of 1RM (Repetition Maximum- 14.2%), RFD (Rate of Force Development- 16.7%), CE (Cycling Economy- 4.8%), work efficiency (4.7%) and time to exhaustion at pre intervention maximal aerobic power (17.2%). However no changes were observed in VO2 max or body weight. The control group also exhibited some changes in terms of improvement in work efficiency (1.4%). But this change was significantly lower as compared to the intervention group. No further relevant changes were seen in the control group in other parameters. Thus from the study it can be concluded that maximal strength training for a period of eight weeks brought out significant changes in the Cycling economy and efficiency and increased the time to exhaustion at the maximal aerobic power, without much change in maximal oxygen uptake, cadence or body weight (Sunde et al., 2010). In a separate study conducted by Aagaard et al., they supported the point that strength and endurance training improves cycling economy remarkably. They also concluded that strength and endurance training lead to an improved 45- min time- trial endurance capacity which was also accompanied by increase in proportions of type IIA muscle fibres and improvements in muscle strength and rate of force development (Aagaard et al., 2011).
PRESENCE OF TYPE 1 MUSCLE FIBRES: Cycling economy also relates largely to the presence of a particular muscle fiber. This theory was proved in a research study conducted by Coyle, Sidossis, Horowitz and Beltz. Type 1 muscle fibers were identified for this research by undertaking multiple biopsies of the vastus lateralis muscle. These fibres were then grouped as type 1 or type 2 depending upon the histochemical staining for the myosin ATPase activity. This test identifies the myosin heavy chain isoforms. It can be a probability that some of the cyclists who were the participants in the research program, undergoing the multiple biopsies could have the presence of both type 1 and type 2 muscle fibers. However the histochemical staining test was efficient enough to distinguish the two different types of muscle fiber groups. They concluded that muscular efficiency is variable in high- endurance trained cyclists and this variability depends to a larger extent on the percentage of type 1 fibers. Thus when the endurance trained persons perform extension of the knee joint up to 200 degrees per second, type 1 muscle fibers then seem to be more efficiently performing than the type 2 muscle fibers, which could be a result of lower ATP turnover, which is determined by a lower level of VO2, while exercising at a given power output (COYLE, SIDOSSIS, HOROWITZ and BELTZM, 1992).
USE OF NON CIRCULAR CHAIN RINGS: It has been observed that custom made chain rings focusing on increasing crank moment arm or chain ring axis at 3 o’ clock position and reducing the crank moment arm or chain ring axis at the 9 o’ clock position have shown some improvement in terms of cycling economy/ efficiency and performance (Bini and Dagnese, 2012).
BODY POSITIONING: Body positioning affects the energy expenditure during cycling and hence affects the cycling economy too. Air resistance or aerodynamics largely depends on total frontal area of both the rider and the cycle, coefficient of drag and the speed of air during cycling. In a study the amount of oxygen uptake was measured for four different body positions. The cyclists who participated in the test consisted of eight men and 2 women. Each one of them cycled up a 4% incline on a motor driven treadmill in order to overcome the air resistance. The positions that were studied included a) seated, hands on brake hood, cadence 80 revolutions per minute b) seated, hands on dropped bar, 80 revolutions per minute c) standing, hands on brake hoods, 60 revolutions per minute and d) seared, hands on brake hood, 60 revolution per minute. All the cycles were equipped with common set of wheels. The results of this showed that body posture can affect the energy expenditure during an uphill bicycling which was not related to the air resistance (RYSCHON and STRAY- GUNDERSEN, 1991).
AERODYNAMICS: Air retardation is considered to be the most important factor that affects the cycling economy. The aerodynamics of the cyclist and the cycle are the major causes that affect the cycling economy. Thus correct body posture and proper spacing in between the riders can help in increasing the cycling economy and efficiency (Faria, 1992).
CADENCE: While climbing uphill, cyclists prefer low cadence. A test was conducted to check if high cadence provides better cycling economy while going uphill. Nine cyclists were chosen for the tests who were asked to perform steady state bicycling exercise on a treadmill under three random trials. After the test it was concluded that a high cadence uphill cycling gives better cycling economy than a low cadence uphill cycling (SWAIN and WILCOX, 1992). The similar view was also shared by another group of researchers, their research was confined to road cycling only. They also supported the fact that low cadence lowers the cycling economy also, whereas higher cadence increases the cycling economy and efficiency (LUCIA et al., 2004). In another study it was proved that cycling at a cadence of 90-105 rpm is usually preferred by the cyclists as it increases the economy and efficiency of cycling greatly. In this test, seven cyclists were asked to participate. They were made to undergo different sessions in order to determine the uptake of oxygen and release of carbon dioxide by them. Eventually the results again supported the theory of a high cadence being better as compared to the lower cadence rate (Chavarren and Calbet, 1999).
LACTATE THRESHOLD CONCEPTS: It was seen after a series of conducted tests that lactate threshold has a direct relationship with endurance. Which means lower the lactate threshold of the cyclist, lower is the efficiency or endurance (Faude, KIndermann, Meyer, 2009).
ANTHROPOMETRIC FEATURES: Needless to say that a lighter body weight has a greater advantage of providing better results in terms of cycling economy and efficiency as compared to a heavier cyclist. Also a taller individual will be a better competitor than a shorter one. Thus it can be said that bodily features do affect the performance and the outcome.
SADDLE HEIGHT EFFECTS: Studies say that using an angle of 25 degrees to 30 degree knee angle helps in preventing injury during cycling. A study was undertaken with fifteen individuals out of which five were cyclists and the other ten were not. Results obtained from this study, keeping in mind all the required steps and precautions, it was concluded that the angle range from 25 to 30 degrees do prevent the chances of injury to the cyclist. The results were reconfirmed again and again by subsequent number of tests, carried on by different researchers with different setting. The result obtained by all of them was similar and hence convincing enough (Pevler, 2008).
All these factors affect the cycling economy to a great extent. Any alteration in these factors will lead to a decrease in the efficiency or cycling economy. The factors related to the cyclist, the air and the cycle, all play major roles in defining the economy of the cycling. Fault on part of any of these factors will disrupt the efficacy of the cycling. These factors are interdependent and affect the outcome to a larger extent. Efficacy of any two and lack of the third one will disrupt the results very badly. For instance, strength training if not done adequately will provide lesser cycling economy even in the perfect air conditions and with the best cycling equipments. Similarly, if aerodynamics is unsupportive of a good economy then the best efforts by the cyclist and the best equipped bicycle will not give the desired results. The cyclist’s strength will greatly be affected by his anthropometric dimensions, muscle fibers and their types, endurance level and so on.
The effect of lactate is also a significant theory. Higher is the lactate threshold, obviously higher is the cycling economy. Lactate is the by- product of anaerobic respiration within the muscles. After the muscles consume all the available oxygen, they start performing respiratory functions anaerobically. This leads to accul\mulation of lactate or lactic acid in the muscles. This lactic acid has a tendency to cause cramping pains in the affected region. Some people have a tendency to develop lactic acid faster than others. These people, if they take cycling as a profession, need to train themselves adequately to decrease the chances of lactic acid formation. Decreased lactic acid synthesis will decrease the chances of muscle fatigue and hence the cyclist can perform better and for a longer period. Or we can say that his endurance will thus improve. Hence it can be claimed that lactate has a great role to play in increasing or decreasing cycling efficiency or economy of a cyclist.
General physical strength and endurance of the cyclist will also affect his performance. Proper training and physical exercises can strengthen his body and help him perform better. A fitter and leaner cyclist will definitely be able to give a better outcome than the opposite one.
Equipments also have a role to play. Certain changes in the equipments, updating of the equipments according to the latest technological changes and using proper helmets, gears and other accessories can improve the performance of the cyclist to an unimaginable extent. Therefore it can be said that cycling economy or efficiency is a multi factorial subject; lots of things affect the results directly or indirectly, the impact of these factors can be variable both in terms of impact and extent. Each factor has an important role to play, every factor has its own importance and credibility. The factors vary and have a bearing on the outcome. alterations of each and every factor affect the results in a way that no other factor can replace the effects of one another. Each factor must be strengthened enough to bring about the best results. A weaker link in any of them can prove to be disastrous for the performance of the cyclist and his efficiency. There should be 100% effectiveness in each of the factor in order to obtain maximum result. Alterations should be taken into considerations and dealt with properly to optimize the result and gain maximum efficiency. Better the dealing of the factors, better are the results thereof, hence they are of utmost importance.

References

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Wikipedia,. (2015). Stationary bicycle. Retrieved 23 April 2015, from http://en.wikipedia.org/wiki/Stationary_bicycle