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• New and old: enjoyment of free air
  Martin Hofmeister
  Published on: 11 October 2022
• Stand up for better research - avoiding cherry picking when reporting results
  Ulrike Grittner
  Published on: 11 October 2022

• Published on: 11 October 2022

  New and old: enjoyment of free air

  • Martin Hofmeister, Nutrition Scientist (Dr. oec. troph.)

  The German physician Christopher William Hufeland (1762 - 1836) wrote in his famous work 'Art of Prolonging Life' in 1797: "Harmony in the movements is the grand foundation on which health, uniformity of restoration, and the duration of the body, depend; and these certainly cannot take place if we merely sit and think. The propensity to bodily movement is, in man, as great as the propensity to eating and drinking. Let us...

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  The German physician Christopher William Hufeland (1762 - 1836) wrote in his famous work 'Art of Prolonging Life' in 1797: "Harmony in the movements is the grand foundation on which health, uniformity of restoration, and the duration of the body, depend; and these certainly cannot take place if we merely sit and think. The propensity to bodily movement is, in man, as great as the propensity to eating and drinking. Let us only look at a child. Sitting still is to it the greatest punishment. And the faculty of sitting the whole day, and not feeling the least desire for moving, is certainly an unnatural and diseased state. We are taught by experience, that those men attained to the greatest age, who accustomed themselves to strong and incessant exercise in the open air. I consider it, therefore, as an indispensable law of longevity, that one should exercise, at least, an hour every day, in the open air."

  Conflict of Interest:

  None declared

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  Conflict of Interest:
  None declared.

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• Published on: 11 October 2022

  Stand up for better research - avoiding cherry picking when reporting results

  • Ulrike Grittner, Biostatistician
  • Other Contributors:
    • Sophie Piper, Agnes Fl?el

  With great interest we read Sj?gren et al.'s contribution that analyzed changes in telomere length in association to the time spent exercising and the time spent sitting in a 6-month randomized controlled trial in 49 older sedentary and overweight men and women. Sj?gren et al. concluded that reduced sitting time was significantly associated with telomere lengthening. These findings are of great potential interest, as hi...

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  With great interest we read Sj?gren et al.'s contribution that analyzed changes in telomere length in association to the time spent exercising and the time spent sitting in a 6-month randomized controlled trial in 49 older sedentary and overweight men and women. Sj?gren et al. concluded that reduced sitting time was significantly associated with telomere lengthening. These findings are of great potential interest, as highlighted in the accompanying press release. However, several questions remained for us after carefully reading this contribution: 1. In Figure 1 the associations for change in exercise time and change in telomere lengths for control and intervention group are given. When looking only at those participants with no or positive changes in exercise time, there seems to be a zero or even slightly positive association between change in exercise time and change in telomere length. With regard to the main hypothesis as laid down by the authors, we wonder why participants with reduced exercise time over the course of the study show highest values of lengthening. These are participants who exercised up to 500 minutes per week less at the end of the study than they did at baseline. It would be interesting to see an ANCOVA analysis of both groups combined including baseline telomere length values and baseline exercise time values. This would account for differences in baseline values of each subject and additionally for a possible curvilinear relationship between the change in exercise time and the change in telomere length. 2. Sj?gren et al. stated that they did not find significant associations between changes in steps per day and changes in telomere lengths. It would be helpful to see some descriptive statistics and the test results for that statement. Thus, the reader may get a more comprehensive picture of the study result; e. g., non-significance may just be due to small sample size. 3. The main result of the study is provided in figure 2: associations of change in sitting time and change in telomere length by group. Interestingly Sj?gren et al. only refer to the (significant) result in the intervention group which compiles data from 12 individuals. There is almost no association to be seen in the control group. This raises additional questions: How would the authors explain the differential results for the control and the intervention group? Was change in sitting time related to changes in steps per day or to changes in exercise time? 4. To gain a more comprehensive picture of the associations of interest, additional information as outlined above would be helpful. Furthermore, the role of confounders should be more thoroughly discussed, and results from the entire trial included in the discussion. Generally, it should be avoided to focus only on the subgroup with significant test results (Dwan et al. 2008).

  Getting the information to the points above would shine more light on the association between time spent for sitting, exercising and telomere lengths.

  Reference: Dwan K, Altman DG, Arnaiz JA, Bloom J, Chan AW, Cronin E, Decullier E, Easterbrook PJ, Von Elm E, Gamble C, Ghersi D, Ioannidis JP, Simes J, Williamson PR. (2008). Systematic review of the empirical evidence of study publication bias and outcome reporting bias. PloS one, 3(8), e3081.

  Conflict of Interest:

  None declared

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  Conflict of Interest:
  None declared.

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