Fitness

I am a 5'10" male at 148 pounds with a 5 percent body fat.  I am 23 y/o.  For almost four months now i have lifted weights about 3 times a week for about a half hour to an hour and ran 3-5 times a week for 15-30 minutes.  I am trying to gain muscle.  I feel like i am eating CONSTANTLY and still am having trouble putting on weight.  Any suggestions?

 What's your current lifting program? What's your current calorie intake? Typical menu?

 And knock it off with the running - more than 90 minutes of cardio a week makes it hard to put on muscle.

yeah if you're only trying to put on weight don't bother running.

Melkor, if you're doing HIIT does that also make it hard to put on muscle? I have a hard time keeping my 1300 calorie allowance so I usually end up around 1500-1600 and need that cardio to get a deficit :/

Depends - but if you can survive doing 90 minutes of HIIT a week, I expect to see you on the short list of entrants for the next Olympics :)

 HIIT or other sprint-type workouts have benefits that steady-state cardio doesn't have; it's better for fat loss than steady state, and it doesn't interfere with muscle gain to the same extent.

 I'd still keep total duration to 90 minutes/week - but that's not really a limit; last time I did HIIT I felt like I was about burst a kidney with effort after about 5 minutes.

 'Course, my allergies play a role in that, but still - if you can do 30 minutes straight of hill sprints you're probably just out of Navy SEAL training ;)

Maybe I'm doing HIIT wrong then...I have been trying to find programs online since no one I know knows what that is and I mainly work out with guys that play basketball for their cardio which is pretty much like HIIT since you have to sprint...anyways...I do steady running (6.0) for 15 minutes and then sprint for 60 seconds and then walk for 60 seconds or so and do that three more times. Apparently I should do something else?? Im still exhausted when I'm done and that says a lot since I'm a reformed cardio-only 4-5 miles 5 days a week person :)

Try this HIIT workout plan from Shawn Phillips - you work your way up to 15 minutes over a period of 8 weeks :)

 'course, that's 30 seconds of "oh-gods-my-lungs-are-about-to-explode"-level sprinting alternated with 30 seconds of jogging - an even nastier version is the Tabata protocol. In the original study by Tabata, he had college varsity athletes and Olympic speed skaters on the Japanese skate team literally puking on the lab floor from the intensity - you don't need to go at it that hard!