In this work, we present a way to improve piezoresistive MOSFET strain gauges using Lock-In principle. This reduces the influence of 1/f-noise, showing a Limit of Detection (LoD) reduction from 474 (42) μϵ for current measurements to 40.5 (15) μϵ for Lock-In measurements at 10 μA (100μA) bias. This 1/f-noise reduction also allows for using more efficiently averaging, leading to a 50-fold improvement from 387 (30) μϵ for current measurements to 7.8 (2.4) μϵ for Lock-In, with 100 samples averaging.