biology reading site image no navigation Critical reading banner
spacer gif

Methods

As you learned in the General Reading Strategies section the methods of a research article consists of several elements such as Population or Participants, Research Design, Procedures and Statistical Treatment. There may also be tables or figures describing aspects of the methods. You can ask critical questions about these elements to determine whether the research was carried out appropriately and whether it would be replicable. Generally, the method used to obtain results for a particular study must be valid, that is it must conform to current procedural norms for the particular area being researched. It must also be reliable, which means that it should be the appropriate method to be used given the demands of the study. A particular method may be valid yet unreliable for the purpose of the study.

Following is some of the methods section from the article: Hadjicharalambous, M., Georgiades, E., Kilduff, L. P., Turner, A. P., Tsofliou, F. and Pitsiladis, Y. P. (2006) Influence of caffeine on perception of effort, metabolism and exercise performance following a high-fat meal, Journal of Sports Sciences, 24:8,875-887.

Click on both the question button icons to see the kinds of critical questions you could ask. You will need to click on the icons more than once to reaveal all the critical questions. Consider your answers to these critical questions then click on "See Answers" to see our answers.

Methods stage Part of the method Critical questions

PARTICIPANTS

Eight endurance-trained male athletes (age 27, s = 4 years; height 1.78, s = 0.06 m; body mass 73.7, s = 7.8 kg; maximal oxygen uptake [VO2max] 57, s = 5mlmultiplied bykg -1multiplied bymin -1) and ten endurance-trained male cyclists (age 25, s = 6 years; height 1.82, s = 0.07 m; body mass 74.3, s = 8.6 kg; [VO2max] 62,
s = 5mlmultiplied bykg -1multiplied by min-1) volunteered to participate in Experiment 1 and Experiment 2, respectively. All participants gave their written informed consent to take part in the study, which was approved by the local research ethics committee.

question mark button

The sample size is very small and this may affect the interpretation of the results.

No, and it should be. Also, how did participants ‘volunteer’? How biased was the sampling?

The rationale for this is not given and should be set up in the introduction. What does endurance training involve?

With this research design, possibly yes, to give more weight to the results and statistical analysis.

No - we need to know why participants were chosen with these characteristics.

EXPERIMENTAL DESIGN

For both experiments, participants initially underwent ramp incremental exercise (15 –20Wmin-1) to the limit of tolerance, using an electrically braked cycle ergometer (Experiment 1: Excalibur Sport, Lode, The Netherlands; Experiment 2: Bosch Erg- 551 Forckenbecksti, Berlin, Germany), to determine VO2max and the maximal work rate. Participants were required to undertake three exercise tests in both Experiment 1 and Experiment 2. In Experiment 1, participants cycled at an ambient temperature of 20°C for 30 min at a work rate equivalent to 63% of each individual’s maximal work rate, which was immediately followed by a 15Wmultiplied bymin-1 ramp to the limit of tolerance. In Experiment 1, each consecutive test was separated by at least one week. In Experiment 2, participants cycled to exhaustion at a similar work rate to that in Experiment 1.

The participants underwent at least two familiarization trials before the three exercise tests, to familiarize them with the exercise protocol and experimental procedures. During the familiarization period (i.e. 3 days before the second familiarization trial), each participant’s normal energy intake and diet composition were determined from weighed dietary intake data, using a computerized version of the food composition tables of McCance and Widdowson (revised by Holland et al., 1991). Based on this information, participants were prescribed a high (70%) carbohydrate diet throughout the study period, intended to increase and maintain liver and muscle glycogen concentrations before each of the main exercise trials (Bergstrom, Hermansen, Hultman, & Saltin, 1967). The 70% carbohydrate diet was isoenergetic with each participant’s normal daily energy intake, and food items prescribed were based predominantly on each participant’s normal diet.

Four hours before the first exercise test in both Experiment 1 and Experiment 2, the participants consumed a standardized high carbohydrate meal (90% of energy intake in the form of carbohydrate [control trial]). In both experiments, the control trial was always performed first. Consequently, this trial was not included in the randomization, and hence in the statistical analysis. Four hours before the second and third exercise tests, the participants consumed a standardized high fat meal
(1 g fatmultiplied bykg.body mass; 90% of energy intake in the form of fat). All experimental meals were isoenergetic and prepared by the same investigator. One hour before exercise following the high fat meals (second and third tests), the participants ingested, in a cross-over double-blind manner, capsules containing caffeine (Experiment 1: 7 mgmultiplied bykg-1 body mass; Experiment 2: 7.5 mgmultiplied bykg-1 body mass [fat + caffeine trial]) or an equivalent amount of placebo (calcium carbonate [fat-only trial]).

Participants were required to maintain normal dietary and training habits throughout the study period, but to refrain from strenuous training and consumption of alcohol or caffeine-containing products in the 48 h prior to each exercise test.

question mark button

No, there needs to be further information provided as to why these subjects were chosen and why experiment 1 and 2 were designed in this way and what will be the significance of the results obtained.

No!

No!

Probably yes, but more explanation of the experimental design is required.

See answers