What you learn, you forget 50% of it within 60 minutes and only retain 20% after a month.
The best way to learn and retain longer is reviewing/revising the content regularly and consistently
Brain is also a muscle, the more regularly you use it on some topic with reputation, the better you become at it. Instead of studying once a week for a longer time, try to study in small slots of time regularly and review it over and over again, so that it will penetrate deeper in your brain.
Myself Prem Aseem Jain and my friend Sachi went for the mountaineering trip at Mount Shasta new Sacramento California. We climbed and camped at 10,000 feet at lake Helen for 2 nights and 3 days. We had to carry a tent, fuel, equipment, electronics, food on our backpack. Both of us combined carries around 130 pond weight. There were avalanches, snowstorm, wind storms and temprature was -20 degrees F.
It was fun, when we returned our face had major sun burn.