The relative size of the muonic component in atmospheric air showers is important to infer the composition of the primary cosmic ray and also for the gamma/hadron discrimination. Iron-initiated showers produce more muons than proton-initiated showers. However, we found that below $\sim$1 TeV, the number of muons reaching the detector is larger for proton showers. The reason for that was that the energy of muons produced by low-energy iron showers is not large enough, and many of those muons do not live long enough to reach the detector level. This means that below $\sim$1 TeV, the sensitivity to iron showers, in water Cherenkov detectors, is significantly reduced. This needs to be considered when calculating the cosmic ray energy spectrum at this lower energy range. In this work, we use CORSIKA simulations to quantify the size of the muonic component at the detector level for proton and iron showers as a function of shower energy and for different detector altitudes relevant for SWGO and LHAASO observatories.