An army recruit, smoker and 6 months into training started complaining of pain at posteromedial aspect of both legs. There was an acute point tenderness and the pain was aggravated on physical activity. The most likely diagnosis is -
Information in this question are :-


Patient is an army recruit with 6 months training
Complaining of pain in lower limb
Pain aggravates with activity
Point tenderness


These suggest the diagnosis of fatigue (stress) fracture.
Stress fracture usually occur after a recent change in training regimen has taken place. Especially professional or recreational athletes and military recruits are subject to change in training intensity (increased), type of training or training circumstances (new shoes, other training surface etc) and thus at increased risk of developing a stress fracture.
Bearger's disease
Gout
Lumbar canal stenosis
Stress fracture