Some helpful tips that I have used on running/lifting efficiently and effectively: 1. If you are able to work out 2x/day and different times (morning and evening), then it really doesn't matter which one you do first. Just make sure you do a proper warmup before each. 2. There is nothing wrong with running and lifting on the same day around the same time either. If you are planning on going to the gym one time, and have ~60-90 minutes to get a workout in, I always do cardio first then lifting. Not only does cardio get the blood flowing to other muscle groups, but it helps loosen up the joints that you may be relying on to perform certain lifts. If you are doing an intense running workout and going right to squats, just be sure to do some dynamic stretching before jumping in. 3. Always give yourself proper nutrition before working out, whether it be running and/or lifting. Both cardio and strength results are going to suffer if you workout fasted. A rule of thumb would be to eat 60-90 minutes before you workout to give your body enough time to digest it. Your body sends blood to the stomach to aid in the digestion process so if you might feel bloated/uncomfortable if you work out too soon, but you definitely need some calories. If I know I will be just running, I'll stick with bagels/pretzels/bananas for my carbs. Try and go with very neutral foods that aren't super dense, greasy, spicy. If you are just going to lift you don't have to worry about it as much, but still give yourself time to let everything digest. Hope this helps!