Table 1.
Definitions of variables describing the occurrence and variation of postures in the present study.
| Category & name | Definition |
|---|---|
| Exposure level | |
| LEV1 | Proportion of total time in seated posture (%) |
| Frequency | |
| FREQ1 | Frequency of switches from seated to standing/walking or vice-versa (h-1) |
| FREQ2 | Average duration of uninterrupted periods seated (min) |
| FREQ3 | Average duration of uninterrupted periods standing/walking (min) |
| FREQ4 | Proportion of total time in uninterrupted periods seated longer than one hour (%) |
| FREQ5 | Proportion of total time in uninterrupted periods standing/walking longer than one hour (%) |
| Similarity | |
| SIM1 | Coefficient of variation (SD/mean); durations of periods seated |
| SIM2 | Coefficient of variation (SD/mean); durations of periods standing/walking |
| SIM3 | Correlation between the duration of periods seated and the following period standing/walkinga |
| Criteria basis for compliance with guidelines | |
| CRIT1 | Average time until 5 minutes of standing/walking have been accumulated (min)a; b |
| CRIT2 | Average time until 5 minutes of uninterrupted standing/walking have been obtained (min)a; b |
| CRIT3 | Average time until 10 minutes of standing/walking have been accumulated (min)a; b |
| CRIT4 | Average time until 10 minutes of uninterrupted standing/walking have been obtained (min)a; b |
| CRIT5 | Proportion of total time when standing/walking has not occurred for 5 accumulated minutes during the previous hour (%)c |
| CRIT6 | Proportion of total time when standing/walking has not occurred for 5 uninterrupted minutes during the previous hour (%)c |
| CRIT7 | Proportion of total time when standing/walking has not occurred for 10 accumulated minutes during the previous hour (%)c |
| CRIT8 | Proportion of total time when standing/walking has not occurred for 10 uninterrupted minutes during the previous hour (%)c |
a Analysis begins by first period seated, disregarding any possible standing/walking period in the very beginning of the recording.
b When a period containing the necessary standing/walking time has been obtained, time count restarts at the next following occurrence of sitting.
c Exposure time-line analysed using a 60-minute moving window at one second increments. Ten minutes preceding the start of the actual recording was considered to be standing/walking, since the recording equipment was attached while the subject was standing.