• If you're swimming before the run, it could just mean you're getting tired, so you should definitely try the run on "fresh" legs (or at least try the "triathlete" kick when you swim, which means not kicking much at all).

• For longer runs, you should seriously consider refueling midway. Sport gels/beans contain electrolytes to replace what you've lost sweating as well as sugar which your body can quickly convert to energy.

• Also, this tends to vary from person to person, but if I'm going on a long run, I always make sure to eat well a couple hours beforehand. I like to load up on whole wheat toast, high-protein cereal, milk, sometimes eggs. The carbs will give you energy and the protein and fiber keep you full.

• Keep in mind that you do need a fair amount of strength to run longer distances and running isn't the quickest way to build this strength. Do you ever spin with a lot of resistance/cycle up hill? It does wonders building quad strength. I'm a huge fan of spinning because it's a great workout and a great way for runners to cross train and I really credit the spinning for getting my mileage up. Also, do you lift weights? You'll want to make sure to work your shins (sitting on a bench with your legs in front of you and your lower calves/feet hanging off the edge, hook a weight over your feet and move it up and down) as well as your calves (you can use the Smith machine with a step or just stand on stairs or on your toes and raise and lower your body). Squats/lunges are another good way to work your quads. If you're not familiar with these exercises and have a gym membership, it's worthwhile to have at least a session or two with a personal trainer so they can show you the correct way to do them.

Good luck -- I'm sure you'll get over this hump in no time!

1st what pace are you doing your distance runs at? Maybe your problem is you are running too fast. the purpose of slow distance runs are to build up blood capillaries and cell mitochondria for your faster runs/races.

there are various formulas to determine slow distance runs, Jeff Galloway has a formula, can't put my hands on his book so this will be from memory.

do a time trial mile, warm up is something like a 1/2 mile slow jog then run your mile. take that time plus 1.2 for a 1/2 marathon race pace and then you add 3 mins on that for your slow run pace.

so for simple math example: mile time 10:00 min, 12:00 min pace for 1/2 marathon, slow runs would be 15:00 min pace you could also try to come up w/ this number by taking what you think your race pace will be and add 3 mins for slow distance run time,

If you are planning on doing race at 9:00 min pace, slow would be at 12:00. it IS hard to run as slow as the formula but think you will be able to finish the distance w/ that advice and the other tips. also, sometimes just altering your pace, speed up/slow down helps as does change of terrain. if you are running all on flat that gets fatigueing.

definitely you need to be drinking along the run and most likely re-fueling after 45 min/1 hr or so depending on the length of your run. also banish the thoughts "I've run xmiles and say to yourself "only 2 miles (or whatever to go) and I've done that a million times before"

I use accel gel and accelerade. sometimes ultima

I did my 1stt ever races this year, 1/2 marathons so if I can do it so can you.....i'm an overwt 54 yr old runner and I'm slow but hey I'd rather run slow at 100 than not at all.

good luck to you