Will the be really benefical to weight loss if i go before work then after work? Is there any reasons not to go twice?

I sometimes work out twice in one day, usually doing cardio in the morning and weight training in the afternoon or evening. I don't think going twice every day is necessary.

Will the be really benefical to weight loss if i go before work then after work? Is there any reasons not to go twice?

The biggest question would be WHAT are you doing in those two sessions? Cardio is fine, but just make sure if you are weight training not to do the same muscle groups twice in the same day. That would be bad, yes. You need the 48 hour break.

I agree with twiceblessed, muscles need time to repair and strengthen. Make sure you don't overwork yourself. Take time off.

There IS such a thing as overexercising...