Absolute Accelerometer-Based Intensity Prescription Compared to Physiological Variables in Pregnant and Nonpregnant Women

Abstract

Estimation of the intensity of physical activity (PA) based on absolute accelerometer cut points (Cp) likely over- or underestimates intensity for a specific individual. The purpose of this study was to investigate the relationship between absolute moderate intensity Cp and the first ventilatory threshold (VT1). A group of 24 pregnant and 15 nonpregnant women who performed a submaximal incremental walking test with measures of ventilatory parameters and accelerations from three different accelerometers on the wrist (ActiGraph wGT3X-BT, GENEActiv, Axivity AX3) and one on the hip (Actigraph wGT3X-BT) were analyzed. Cp were determined corresponding to 3 metabolic equivalents of task (MET), using the conventional MET definition (Cp3.5) (3.5 mL/kg×min) and individual resting metabolic rate (Cpind). The ventilatory equivalent (VE/VO2) was used to determine VT1. Accelerations at VT1 were significantly higher (p < 0.01) compared to Cp3.5 and Cpind in both groups. Cp3.5 and Cpind were significantly different in nonpregnant (p < 0.01) but not in pregnant women. Walking speed at VT1 (5.7 ± 0.5/6.2 ± 0.8 km/h) was significantly lower (p < 0.01) in pregnant compared to nonpregnant women and correspondent to 3.8 ± 0.7/4.9 ± 1.4 conventional METs. Intensity at absolute Cp was lower compared to the intensity at VT1 independent of the device or placement in pregnant and nonpregnant women. Therefore, we recommend individually tailored cut points such as the VT1 to better assess the effect of the intensity of PA.

Changes in self-reported and accelerometer-measured physical activity among pregnant TRICARE Beneficiaries

“…Consistent with past studies [ 12 , 28 ], self-reported activity was typically higher than accelerometer data. One potential explanation for the discrepancy in self-report data, aside from recall bias, may be that the perceived exertion when engaging in physical activity increases as pregnancy progresses, and what is considered inactive pre-pregnancy may be considered active during pregnancy [ 29 , 30 ]. It also may be due to the cutoff points for moderate and vigorous activity being based on non-pregnant samples, and different cutoffs may be needed to adequately assess activity during pregnancy given the changes they are experiencing across gestation.…”

Assessment of physical fitness during pregnancy: validity and reliability of fitness tests, and relationship with maternal and neonatal health – a systematic review

“…Regarding aim 1, 99 tests (including 75 different protocols) were used to assess CRF,8 12 13 18 27–108 28 (including 16 different protocols) to assess muscular fitness,8 12 13 61 86 109–122 14 (including 13 different protocols) to assess flexibility,12 13 110 114 123–127 45 tests (including 40 different protocols) to assess balance,110 116 128–167 2 tests using the same protocol to assess speed168 169 and 3 tests using the same protocol were multidimensional 168–170. No results were found for other PF components such as agility or coordination.…”

Comparison of Outcomes Derived from the ActiGraph GT3X+ and the Axivity AX3 Accelerometer to Objectively Measure 24-Hour Movement Behaviors in Adults: A Cross-Sectional Study

“…Studies comparing 24-HMBs in isolation were also considered but we did not find studies whose results were directly comparable with this study. The comparability of studies reporting on the convergence between ActiGraph and Axivity to measure PA and/or SB was hampered by: (1) the variability in the location where one or both devices were worn (e.g., hip versus wrist) [ 15 ], (2) behavioral conceptualization (e.g., steps versus intensity) [ 16 ], (3) the setting (e.g., field-based versus laboratory) [ 17 ], and (4) the use of different data processing methods (e.g., GGIR versus OMGui) [ 18 ]. Although we found no studies of which the results were generalizable to this study, our results are consistent with the major finding of Rosenberger and colleagues’ (2016) review that several wearable devices are not able to accurately measure MVPA (with the ActiGraph used as criterion measure).…”