Common student misconceptions in exercise physiology and biochemistry

James P. Morton, Dominic A. Doran, Don P. M. MacLaren


The present study represents a preliminary investigationdesigned to identify common misconceptions in students' understanding of physiological and biochemical topics within the academic domain of sport and exercise sciences. A specifically designed misconception inventory (consisting of 10 multiple-choice questions) was administered to a cohort of level 1, 2, and 3 undergraduate students enrolled in physiology and biochemistry-related modules of the BSc Sport Science degree at the authors' institute. Of the 10 misconceptions proposed by the authors, 9 misconceptions were confirmed. Of these nine misconceptions, only one misconception appeared to have been alleviated by the current teaching strategy employed during the progression from level 1 to 3 study. The remaining eight misconceptions prevailed throughout the course of the degree program, suggesting that students enter and leave university with the same misconceptions in certain areas of exercise physiology and biochemistry. The possible origins of these misconceptions are discussed, as are potential teaching strategies to prevent and/or remediate them for future years.

  • prerequisite knowledge
  • metabolism
  • sport science

sport and exercise science (SES) is one of the fastest growing academic disciplines in the United Kingdom. By definition, SES is “the application of scientific principles to the promotion, maintenance and enhancement of sport and exercise related behaviours” (4). From a teaching and research perspective, SES is primarily concerned with the scientific study of sporting performance or that of how regular exercise can promote health and well-being. The subject further encompasses the subdisciplines of physiology, biochemistry, psychology, sociology, biomechanics, and motor learning, to which one of these students will typically direct their attention as their studies develop. Although SES is undergoing rapid growth as an academic discipline, available educational research directed toward improving the teaching of SES within the United Kingdom is limited (18, 19).

Of all the subdisciplines of SES, students typically report they have greatest difficulties when studying exercise physiology and biochemistry, despite these being the most popular areas of SES. This is perhaps not surprising given the factual and conceptual difficulties of the topics and also the rate at which ongoing research is contributing to existing knowledge. For example, the introduction of molecular biology to exercise physiology and biochemistry has presented itself as another major challenge for both student and teacher. Students are now expected to understand whole body physiological responses to acute and chronic exercise while also having an appreciation for the molecular mechanisms underpinning these adaptations.

In teaching exercise physiology and biochemistry disciplines, many lecturers often assume that students are familiar with the “basics” because of they have already satisfied course prerequisites. We assume that because students have completed school or college qualifications in biology, chemistry, or physical education that they will therefore be able to benefit from the teaching of “advanced” content during higher education. On the basis of this assumption, we subsequently devise educational objectives and teaching strategies for the relevant course. We also assume that as students progress through their studies at university, what they learn in modules studied at level 1 will prepare them for level 2 and, finally, level 3. However, when collectively reflecting on our teaching experience, we have frequently observed that merely satisfying course and module prerequisites does not ensure an understanding of basic physiological and biochemical concepts.

The aims of the present preliminary study were to expand the misconception literature [readers of this journal will be well acquainted with such literature (see Refs. 13, 14, 16, 17, and 20)] by attempting to identify those common misconceptions experienced by SES students while studying exercise physiology and biochemistry components of their degree. By distributing multiple-choice questionnaires (and also requesting justification for chosen answers) to level 1, 2, and 3 students, we attempted to track the prevalence of these misconceptions throughout their degree progression.


Misconceptions inventory.

At a meeting of the authors, a “list” of common misconceptions on various aspects of exercise physiology and biochemistry was compiled. This list was drawn from the authors' previous experiences of interacting with students in the classroom and office and from formal marking of coursework tasks and examinations. Statements of these misconceptions are shown in Table 1. These misconceptions were subsequently incorporated into a questionnaire that presented 10 multiple-choice questions detailing those misconceptions outlined in Table 1. Students were also provided with space to justify their reasoning for their answers so as to provide the authors with a further understanding of any misconceptions identified. The “Misconceptions Inventory” questionnaire is shown in Table 2 together with a full breakdown of student responses.

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Table 1.

Potential student misconceptions on aspects of exercise physiology and biochemistry as recognized by the authors' experiences of teaching these topics

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Table 2.

Summary of student responses

Populations surveyed.

A sample of students enrolled in physiology- and biochemistry-related modules in the BSc (Hons) Sports Science degree at Liverpool John Moores University participated in the investigation. Students from levels 1 to 3 participated in the study so as to gain an understanding of the prevalence of any misconceptions throughout the course of the degree program. Students were not asked to volunteer, and the exercise was presented as a compulsory part of the course, which served to act as a catalyst for promoting revision for end of year examinations. Demographic information of the students studied is shown in Table 3, along with their educational background.

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Table 3.

Description of the student population surveyed


Of the 10 misconceptions proposed by the authors, 9 misconceptions appeared to be prevalent among the populations studied (there was no evidence of any misconceptions regarding brain blood flow during exercise; data not shown). The percentage of the student population at each level of study who displayed misconceptions is shown in Table 4. A comprehensive analysis of student answers is also shown in Table 2.

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Table 4.

Percentages of students at each level of study who displayed a misconception in understanding to questions 1-9

Lactate misconceptions.

The data demonstrated that 85%, 80%, and 60% of the population studied at levels 1, 2, and 3, respectively, responded with a misconception concerning the understanding of cellular conditions that result in lactate production during muscle contraction (question 1). In relation to the function of increased lactate production (question 2), there was a linear decrease in the prevalence of misconceptions from levels 1 to 3. In general, students at levels 1 and 2 misconceived lactate to be a dead-end waste product that causes fatigue or will produce hydrogen ions that cause fatigue. In level 3, only 19% of the population responded with a misconception, whereas 81% of students correctly understood lactate to be an important energy-yielding substrate. These data demonstrate that as lactate metabolism is studied in more detail as the degree program progresses, students successfully appreciate lactate as a metabolite as opposed to a possible fatiguing agent. Nevertheless, students do not appear to appreciate or become aware that lactate can also be produced during oxygenated conditions.

Fat metabolism misconceptions.

Misconceptions concerning the optimal exercise intensity to oxidize lipids during exercise (question 3) were made by 44% (level 1), 43% (level 2), and 72% (level 3) of the population studied. Greater than 95% of the population at levels 1-3 showed misconceptions regarding the interaction of fat and carbohydrate metabolism during exercise (question 4). In this situation, all students clearly misconceived that skeletal muscle will only utilize fat as a fuel source during exercise when carbohydrate stores have been reduced due to depletion of muscle glycogen, blood glucose, or a combination of both.

Muscle contraction misconceptions.

In relation to the process of muscle contraction (question 5), 84% (level 1), 75% (level 2), and 90% (level 3) of the student population responded with answers A–D, which focused solely on peripheral processes. This question, however, may have been misunderstood by students, as only 6% (level 1), 25% (level 2), and 10% (level 3) of the population correctly chose answer E (“other”), where all of these students correctly explained that muscle contraction begins with an impulse from the brain. It is acknowledged that if this option had been explicitly available for selection (as opposed to “other”), more students may have chosen this answer. Nevertheless, these data demonstrate that only 6–25% of the students appreciated the importance of the central nervous system in voluntary muscle contraction. In answering question 6, 56% (level 1), 50% (level 2), and 57% (level 3) of students responded with a misconception concerning what happens to components of the sarcomere during a shortening contraction. In these instances, the majority of misconceived responses assumed that the A-band will also shorten during a contraction. Approximately 50% of all students, therefore, do not appear to understand the mechanics of muscle contraction.

Determinant of endurance performance misconceptions.

Misconceptions concerning the most important predictor of endurance running performance (question 7) were made by 63%, 84%, and 68% of level 1, 2, and 3 students, respectively. The most prevalent misconception was that maximal oxygen uptake (V̇o2 max) is the most important determinant. Only 37% (level 1), 16% (level 2), and 32% (level 3) of the population correctly cited the lactate threshold as the most important determinant of endurance performance.

Oxidation reaction misconceptions.

Misconceptions concerning the nature of an oxidation reaction (question 8) were made by 81%, 61%, and 67% of level 1, 2, and 3 students, respectively. The most prevalent misconception was that oxidation reactions involve the loss (or gain) of an electron solely from (or by) an oxygen molecule. Students therefore appeared to misconceive that any biological substance can be oxidized or that oxidation reactions are the loss of an electron (as opposed to gain) from the particular substance.

Blood pressure regulation misconceptions.

Misconceptions concerning blood pressure responses during exercise in hot ambient conditions that induce dehydration (question 9) were made by 78%, 54%, and 80% of level 1, 2, and 3 students, respectively. These data demonstrate that students do not appear to understand how blood pressure is regulated and responds to exercise.


The aim of the present preliminary study was to identify common misconceptions in students' understanding of physiological and biochemical concepts of SES. Using a specifically designed multiple-choice questionnaire, the present data identified nine misconceptions in understanding. Of these nine misconceptions, only one misconception appeared to have been alleviated by the present teaching strategy.

Potential sources of misconceptions.

Potential sources of misconceptions are often quoted as having arisen in the classroom, from textbooks or from an experience in the “real world” (13, 16). It is difficult to precisely state the origins of the misconceptions identified here, and it is also possible that sources may be different between the level 1–3 populations sampled. For example, the level 1 students studied here had not been exposed to any “exercise” science during their first year of study but rather were exposed to those “physiological foundations” deemed necessary before embarking upon “exercise physiology” in level 2 study. In this regard, it is tempting to speculate that misconceptions identified in level 1 students may be simply due to no previous knowledge (or exposure) of exercise science. Misconceptions in these students may have therefore arisen from experiences outside of the classroom. However, considering that >50% and >70% of this population had completed school or college study in biology and physical education, respectively, it is somewhat concerning that students entered university with large misconceptions in areas such as mechanics of muscle contraction, lactate metabolism, and integration of lipid and carbohydrate metabolism. Furthermore, it is even more worrying that misconceptions were still prevalent in level 2 and 3 study, despite the increased emphasis on exercise science as the curriculum developed. Misconceptions in lactate metabolism appeared to have been somewhat alleviated from the present teaching approach, although there is still definite room for improvement. Nevertheless, the prevalence of misconceptions from level 1 to 3 study indicates that the present classroom and laboratory teaching strategies do not appear to be achieving the the desired outcomes. In agreement with Michael et al. (16), it is clear “that something we do or say in the classroom or include in our written materials” will contribute to students developing a misconception.

One such activity has been suggested to be the imprecise use of language by teachers and students (22). Jacobs (8) also noted that every science discipline uses terms from everyday (lay) language that have special meanings within the discipline, e.g., elasticity. Incorrect use of such terms may therefore lead to the formation of a misconception. Visual representations in the classroom (22) and oversimplified analogies (6) have also been proposed as origins of misconceptions in science. With this in mind, it is apparent that we must strive for precision and clarity in our words (or visual aids) so that what we seek to communicate is actually what is communicated.

In addition to “classroom practices,” it is also possible that many misconceptions may be due to conflicting research literature or “ill-informed” and “vaguely” written textbooks. This may be particularly the case with some of those misconceptions identified here, such as lactate metabolism and determinants of endurance performance. For example, the function of lactate was the subject of a “Point-Counterpoint” debate between established researchers in recent editions of the Journal of Applied Physiology in 2006 (1, 911). Furthermore, some authors still cite V̇o2 max as the most important determinant of endurance performance (12) despite the wealth of research evidence supporting the lactate threshold as the most important predictor (2). In a similar manner to teachers in the classroom, textbook authors should also strive for precision and clarity in their words when drafting texts. Having an awareness of common misconceptions and an appreciation of students' understanding would appear to be a good starting point when undertaking the writing process.

Experiences outside of the classroom have also been postulated as possible sources of misconceptions (16). This could potentially be the case with the present study with areas such as lactate and fatigue or with integration of lipid and carbohydrate metabolism. For example, many sports commentators and members of the general public frequently report buildup of lactic acid as a cause of fatigue during competition. The wealth of advertisement campaigns promoting the importance of carbohydrate sport drinks for optimal performance also create the perception that lipids are not an important fuel source during sport and exercise. It is, of course, difficult to say whether reasons such as these are the origin of those misconceptions identified here. Nevertheless, as teachers and scientists, we have the responsibility to correctly inform the general public and media of relevant research findings.

It should also be noted that many of the students studied here exhibited correct answers to the multiple-choice questioning but upon justifying their reasoning were unable to provide evidence of understanding behind the topic in question. In such circumstances, the extent of the misconception identified therefore appears underestimated. In agreement with Michael et al. (17), we also observed that students may “understand” less than they appear to “know.” These data suggest that students may have been able to memorize a particular fact they have read in a textbook or heard in the lecture theater but have not developed an understanding of how the fact has arisen.

Regardless of the precise source of the misconception, it is essential that we are aware of the existence of the misconception in the first instance. Indeed, it is possible that many of the current teaching staff involved in delivering those modules in question in the present study may have been unaware of the presence of the misconception. Furthermore, if not aware of such basic misconceptions, it is likely that such staff therefore pitch the lecture at a level that is beyond the current level of student understanding. Formal identification of misconceptions would therefore seem an appropriate and invaluable introductory activity for which to implement to understand the learner's needs and current level of understanding while also promoting an aligned curriculum.

Potential teaching strategies.

Once a misconception has been identified, the logical progression is to formulate teaching strategies to remediate and/or prevent a reoccurrence for future years. Suggested teaching approaches include active laboratory experience to provide an understanding of the particular phenomena and also an interactive learning environment in the classroom (3, 15, 21). Where students do not have access to appropriate laboratory instrumentation, it has also been suggested that “teaching with classic papers” can lend itself to the exercise physiology and biochemistry discipline. For example, Brown (5) reported how teaching with the classic paper of Gollnick et al. (7) was especially useful for illuminating the exercise-specific differences in bioenergetic enzymes, muscle fiber type, and fitness characteristics that exist between untrained and trained individuals. Given the nature (and also the interrelationships) of the misconceptions identified here, all of the above approaches appear suitable.

Limitations of the study design.

The present study may be limited in terms of the wording of questions in our Misconceptions Inventory. For example, we have previously discussed how the wording of the question relating to contractile processes may have confused the student. It is also possible that the question testing students' understanding of when lactate was made was misleading given that students may have interpreted this to mean “predominantly” made. Clearly, we should strive for precision and clarity in our wording and also design questions that more directly test the misconception being targeted. For example, in this instance, it would have been more beneficial if such a question had graphs depicting what happens to the lactate concentration under conditions of hypoxia, normoxia, anoxia, and exercise so as to more robustly test students' understanding of lactate production.


This study represents the first known attempt to undercover some of the misconceptions that SES students may have when studying physiology- and biochemistry-related areas of the progression of their degree. It is only when we can understand our students' current levels of understanding can we begin to formulate teaching strategies to facilitate meaningful and successful learning. Formative assessment of relevant topics via online multiple-choice questioning (delivered at the beginning of a particular module or at appropriate points of study) may be one potential user-friendly avenue of how to obtain such information. These data also demonstrated that students may appear to understand less than they know, and, in this regard, it is essential that we focus on implementing teaching learning activities that develop thought and understanding rather than making students remain as passive recipients of facts. An interactive classroom environment, active laboratory experience, carefully chosen assessment tasks, and a well-aligned curriculum would appear to be essential activities for such higher-order learning to take place. Finally, once we understand the level of understanding of our students, it should be our duty as educators to provide comprehensible, easy-to-follow, integrative, and affordable texts to serve the undergraduate student population. Given the current direction of exercise physiology and biochemistry research, such texts should be drawn from a variety of scientific disciplines (e.g., molecular biology, biochemistry, and physiology) and deal with various levels of chemical organization (molecular to organism).


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