Treadmill Tiredness

A man of your size should be eating at least 2500 calories to LOSE weight. I'd assume it's the general lack of appropriate fuel.

While I agree you need more food, I'm curious of the days that are "fine" are early in the week and the days where you're dragging are later in the week? If so, maybe 5 consecutive days is too much for now-stick with 5 days but split them up so you've got a day off in the middle (like mon, tues, wed, fri & sat with Thursday & Sundays off). Eat more regardless, but if you do better earlier in the week than later, try splitting up your days.

When I started doing HIIT on the treadmill, I found that I felt fatigued if I didn't fill up beforehand on complex carbs first.

It might also be that in addition to not having enough carbs, you are doing treadmill runs too frequently in a row. Your body needs time to adjust to the routine of working out 4+ times a week. I also found in my own experience that I couldn't run more than 4x a week the first week.. after resting for a few days, I was able to consistently run 5x or more a week.

Assuming a goal weight of 280 abd 30% bodyfat, these are your numbers to LOSE (at least 3000 calories based on you activity level)

Activity Level Daily Calories
Sedentary (little or no exercise, desk job) 2387
Lightly Active (light exercise/sports 1-3 days/wk) 2735
Moderately Active (moderate exercise/sports 3-5 days/wk) 3083
Very Active (hard exercise/sports 6-7 days/wk) 3431
Extremely Active (hard daily exercise/sports & physical job or 2X day training, i.e marathon, contest etc.)

Ignore them....from actually looking at your diary you are eating 1600+ exercise calories. People seem to believe that only TDEE/BMR works. While I am a big supporter of TDEE/BMR, you are using MFP correctly and how it should be used...so ignore them.

But, looking at you diary I do notice that you are lower carb yes? May I suggest maybe eating more carbs on the days your run. Carb fuel runs, that is why people who run triathelons and marithons carb load before races, and take carb shots during. I generally max out my carbs on running days.

I find it useful to break up the treadmill runs. Of course, I break it up with more exercise.
Usually I'll do 10-minute intervals with sets of push-ups or sit-ups in between, that way I find myself looking forward to the break from the treadmill and I push other exercises to a point where I am looking forward to getting back on the treadmill!
I got a little flat screen TV to put in front of the treadmill and connected it to DVD, VHS, media player, DVR and TV... so I can keep my mind off the exercise and keep going.

I will normally do 4 days a week, 2 treadmill runs a day at 100 minutes each breaking one up with sets of push-ups and the other with sets of sit-ups. The other 3 days I will do 1 treadmill run and a 2-hour karate class.

Reading through the thread, there's some really good nutrition information regarding the physical activity, probably things I will also try to incorporate. I am guessing my weight loss has stagnated because I lack the nutrition aspect and have more of a 'cut calories, increase activity' mentality, but I find myself increasing activity and eating too much at night.

I do it Monday thru Friday and take weekends off. My diary is public, I eat most of my calories and I am doing 1600 a day.

Yes, you need more food! I am a 5'5 female and have been losing about a pound a week eating 1600 calories per day. You're not fueling yourself enough for your workouts, which is why you are tired.

Thank you. As a 4'11 female and 40% of the OPs weight, I wouldn't even eat 1600 calories to lose. 1700+ for me and I'd assume we burn a similar number of calories in our workouts.