Hi there. A person gains weight when there is less calorie expenditure than intakevor when basal metabolic rate is less.
As u told u work out more....if u r working in gym setup, then change to yoga.
As far as Ayurvedic medicines, take the following.
1. Ajashwagangha lehyam 2tsp. after food in morning.
2. Weekly once oil application to body with balaswagandhadi taila followed by hot water bath.
3. Eat peacefully.
4. Ensure u take atleast 250 ml full fat milk.
Try doing this for 1 month and get back to me.