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Introduction, aims

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In this exercise you are asked to answer some critical questions and evaluate the argument in the introduction of an article by Wiles, J. D., Coleman, D., Tegerdine, M. and Swaine, I. L. (2006) The effects of caffeine ingestion on performance time, speed and power during a laboratory-based 1 km cycling time-trial, Journal of Sports Sciences, 24:11,1165 — 1171.

Answer the critical questions for each stage of the introduction. When you have finished click on the Submit button to check your answers.

Stage and purpose of stage Stage of the introduction Critical questions
1. ESTABLISHING THE FIELD

- asserting importance of the topic


- stating current knowledge (generally)

According to the research literature, the effects of caffeine ingestion on the full continuum of exercise performance (relating to an improvement in speed and hence a reduction in time taken to complete an athletic event) remain unclear (Graham, Hibbert, & Sathasivam, 1998; Nehlig, Daval, & Derby, 1992). Whereas the effects on "aerobic" performance are reasonably well established (Costill, Dalsky, & Fink, 1978; Falk et al., 1989; Ivy, Costill, Fink, & Lower, 1988; Trice & Haymes, 1995, Van Soeren & Graham, 1998), the research evidence for the effects on "anaerobic" performance are somewhat more equivocal. Although part of the problem can be attributed to the lack of consistency in caffeine dosage, exercise procedures and training status of participants, there also appears to be a lack of published research on some aspects of the effects of caffeine. Early studies of the effects of caffeine on all-out exercise of short duration (cycling for about 15 s) showed no improvement in power, work or fatigue indices (Williams, Signorile, Barnes, & Henrich, 1988). Subsequently, it was shown that cycling time to exhaustion at 100% maximum was not increased after ingestion of caffeine (Collomp, Caillaud, Audran, Chanal, & Prefaut, 1990). More recently, Greer, McLean and Graham (1998) also showed that caffeine ingestion did not affect cycling performance during four 30 s bouts of cycling with 4 min rest between bouts. These findings were further substantiated by the work of Bell, Jacobs and Ellerington (2001), who found no improvement in 30 s Wingate performance after caffeine ingestion (5mgmultiplied bykg -1).

Has the topic been clearly established?
Yes 
No 
        yes is correct       

Has current knowledge of the topic been sufficiently covered for this stage?
Yes 
No 
        yes is correct       

Are the key researchers in the field referred to?
Yes 
No 
        yes is correct       

Do the authors provide you with a good overview of past knowledge of the topic?
Yes 
No 
        yes is correct       

2. SUMMARISING PREVIOUS RESEARCH

- from the perspective of this research

However, others have shown that caffeine improves performance in short-duration high-intensity exercise. Collomp, Ahmaidi, Chatard, Audran and Prefaut (1992) showed improved 100m swimming performance, of about 60 s duration, in trained but not in untrained swimmers. Anselme, Collomp, Mercier, Ahmaidi and Prefaut (1992) showed improved maximal anaerobic power derived from a force - velocity cycling test. Interestingly, Bell et al. (2001), using healthy male participants, did find that caffeine significantly improved time to exhaustion in a maximum accumulated oxygen deficit (MAOD) test (performed at 125% VO2peak) that lasted about 2min. Similar findings for MAOD time to exhaustion were reported by Doherty (1998) and Doherty, Smith, Davison and Hughes (2002), who found that an acute dose of caffeine (5mgmultiplied bykg -1) improved time to volitional exhaustion by more than 10% in trained males during a treadmill running MAOD test (in both cases performed at an intensity equivalent to 125% VO2max). Wiles, Bird, Hopkins and Riley (1992) also showed that 1500m treadmill running performance, lasting about 5min, was improved by the ingestion of caffeinated coffee in trained runners. More recently, caffeine has been shown to improve 2000m rowing performance, which lasted about 7min on average, in competitive oarsmen (Bruce et al., 2000) and oarswomen (Anderson et al., 2000). Therefore, it appears that the effects of caffeine are restricted to all-out exercise lasting more than 15-30 s.

Has previous research been sufficiently reviewed?
Yes 
No 
        yes is correct       

Is the review critical of previous studies?
Yes  No

               no is correct

Is the review being written from the perspective of the authors’ research?
Yes  No

        yes is correct       

Does the review ignore debates in the research?
Yes  No

               no is correct  
3. PREPARING FOR PRESENT RESEARCH
- indicating a gap

- raising a question

While there is some evidence of improved performance after caffeine ingestion in runners and rowers when performing exercise of about 2 – 7min duration, only Collomp et al. (1992) have shown improved performance during exercise of ~60 s duration. As far as we are aware, there are no published reports of the effects of caffeine on performance, speed and power during cycling of 60 s duration in trained cyclists, especially when using cycling-specific ergometry such as with the ‘‘power crank’’ ergometer (Schoberer Rad Meßtechnik, Jülich, Germany).

Does this stage begin to focus on the reasons for the authors’ research?
Yes  No 
        yes is correct       

Do the authors establish a need for the research?
Yes  No 
        yes is correct       

4. INTRODUCING PRESENT RESEARCH AND/OR ARTICLE
 - stating purpose and aims

The aim of this study was to assess the effects of caffeine ingestion on cycling performance time, speed and power during a time-trial of about 60 s duration (1 km) in a laboratory setting.

 

 

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Do the authors lead logically from Stage 3 to their aims?
Yes  No 
        yes is correct       
Are their aims stated clearly?
Yes 
No 
        yes is correct       

Is there a reasonable hypothesis?
Yes  No 
               no is correct