Measurements of ion and electron temperatures on REPUTE-1 ultra-low q (ULQ) and reversed field pinch (RFP) plasmas have revealed that the ion temperature is higher than the electron temperature and that the impurity ion temperature exceeds the hydrogen ion temperature. In ULQ plasmas the impurity ion temperature is correlated with the amplitude of the magnetic field fluctuations observed outside the plasma. A model on ion heating by fluctuations is found to explain the experimental results.