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Introduction With an increasing knowledge of the health benefits from physical activity (PA) the interest in objectively measuring PA in free living environment has increased. ActiGraph is the most commonly used accelerometer to objectively measure PA, while ActivPAL is considered gold standard when it comes to measuring sedentary behavior. Aims The aim of this study was to investigate if ActivPAL could be used to measure Moderate to Vigorous Physical Activity (MVPA) instead of ActiGraph. Methods Data from 79 overweight office workers carrying the ActivPAL and ActiGraph device simultaneously were analyzed. All activities with a cadence of 90 steps per minute (spm) or more lasting for at least 30 seconds from one day from ActivPAL data was extracted and compared to the corresponding activity from ActiGraph. An activity was classified as MVPA by using the cut points of 100 spm for ActivPAL and 3208 activity-counts per minute (cpm) for ActiGraph using vector magnitude (VM). Results A correlation of r=0.326 (p<0.001) was seen between ActiGraph and ActivPAL with a Cohen’s kappa of K=0.14, a percentage agreement of 60.7%, a sensitivity of 61.5% with ActiGraph as denominator and a positive predictive value (PPV) of 84.3% for ActivPAL. Neither age nor BMI affected the association between the estimates by these devices. There was no correlation for time spent in MVPA between devices. Conclusion Cadence from ActivPAL cannot replace ActiGraph to measure MVPA in a free living environment in overweight adults.