One Leg Feels Heavy

Many people have a feeling of heaviness or tiredness in their legs after exercising or spending the day on their feet and wonder “why do my legs feel tired and heavy?”. However, some people experience the same symptoms without exercising or using their legs. These symptoms may be written off as just a normal part of aging, but heavy tired legs could be an indication of an underlying issue, like varicose veins.
https://www.usaveinclinics.com/blog/what-causes-legs-to-feel-tired-or-heavy/