Yes, custom insoles can be used with Newton Running shoes. Many runners find that custom insoles provide additional support and comfort tailored to their individual foot needs. Newton Running designs their shoes with a roomy fit, allowing enough space in the shoe to accommodate custom insoles without compromising the overall fit. This feature can be especially beneficial for runners who may require specific arch support or cushioning that standard insoles do not provide. However, it is important to ensure that the custom insoles do not interfere with the natural feel and performance that Newton shoes offer. Before using custom insoles, it is advisable to try them on with the shoes to gauge the fit and comfort level. For comprehensive information regarding shoes and insoles, it may be helpful to refer to the current webpage that discusses fit and performance.