Team doing singles, what are the benefits?

a bump for me.

When you run at a moderate pace, your slow twitch muscle fibers are the first ones recruited. But if you run far enough, they become glycogen depleted and can no longer contract, so eventually the fast twitch fibers are recruited.

If you do two runs of 6 miles instead of 1 run of 12, then you are taking a break and if you eat between runs (which you probably do) you are refueling your slow twitch muscle fibers with glycogen so that they never become depleted. If they never become depleted, then you never recruit your fast twitch fibers into endurance training. This is also the reason why your long runs need to be at least 22% of your weekly mileage. If you are running 80+ miles, your long run needs to be 18 to 22 miles. Once you run about 16 miles you have depleted your slow twitch fibers, but it is the next 2 to 6 miles in which you are recruiting your fast twitch fibers into endurance training. This is also why staying away from carbohydrates during your high mileage weeks can be benifitial. Carbohydrates are a good source of glycogen.

Nobody except you americans are doing singles, the rest of the world runs 2-3 times a day. Running singles only leads to moderate success. If you really love running what the heck is the problem doing it twice per day.

A few problems with this theory. Fast twitch muscles use glycogen almost entirely(which is stored mostly in your blood and liver not in muscle fiber). Slow twitch muscle is closer to cardiac muscle and are much better at useing stored fat(which is stored in slow twitch fiber) as an energy source.

by the way glycogen stores run out much faster than fat stores, even in very lean well train athletes...remmber health class 4Cal per gram of crabs, 7cals per gram of fat

Sam F wrote:

A few problems with this theory. Fast twitch muscles use glycogen almost entirely(which is stored mostly in your blood and liver not in muscle fiber). Slow twitch muscle is closer to cardiac muscle and are much better at useing stored fat(which is stored in slow twitch fiber) as an energy source.

who came up with the idea of running singles?

Definietly not Lydiard cause all his boys ran 12-13 times per week.Long-Runs are important but not running once per day.

Jesse wrote:

When you run at a moderate pace, your slow twitch muscle fibers are the first ones recruited. But if you run far enough, they become glycogen depleted and can no longer contract, so eventually the fast twitch fibers are recruited.

People have thought this for a long time, but there is no evidence that the FT fibers are recruited during long runs if you continue to run at a slow pace. The FT fibers will certainly be depleted, which leads to adaptations in those fibers, but you'd probably have to pick up your pace near the end of your long runs (or throw in some strides near the end) in order to actually recruit the FT units.

Once a certain average daily mileage is reached, doubles are preferable to singles on a number of fronts (faster vascular development, better recovery/refueling, reduced injury risk, etc.). The mileage breakpoint at which doubles become more advantageous than singles is different from person to person, so you'll have to experiment a bit to find your happy place.

Sam F wrote:

by the way glycogen stores run out much faster than fat stores, even in very lean well train athletes...remmber health class 4Cal per gram of crabs, 7cals per gram of fat

Sam F wrote:

A few problems with this theory. Fast twitch muscles use glycogen almost entirely(which is stored mostly in your blood and liver not in muscle fiber). Slow twitch muscle is closer to cardiac muscle and are much better at useing stored fat(which is stored in slow twitch fiber) as an energy source.

I'm pretty sure it's 9 calories per gram of fat.

Yeah sorry 7g is alcohol, anyway the point is the same

"When you run at a moderate pace, your slow twitch muscle fibers are the first ones recruited. But if you run far enough, they become glycogen depleted and can no longer contract, so eventually the fast twitch fibers are recruited." -Peter Snell, Ph.D (3-time olympic gold, former WR holder in the 800/1500/Mile)

http://www.runnersworld.com/home/0,1300,1-0-0-1963-1-0,00.html

"I always tell runners that, "miles make the champions", and that initially this grind of running all the mileage possible between the competitive seasons is of prime importance. The more miles that you are able to run aerobically in training, then the greater endurance you will be able to develop. So there is really no limit to the mileage that a coach should place upon his athletes, provided that the supplementary miles run above the required faster aerobic running are as easy effort at the lower aerobic speeds. In other words; it is wise to run once a day at faster aerobic speeds and supplementary to this running, to jog as many miles as you find time and energy for; even if it is only for fifteen minutes jaunt." -Arthur Lydiard

http://www.fitnesssports.com/lyd_clinic_guide/lydpg8.html

"I discovered years ago, through trial and error methods, that the best results in this respect were gained by running about 100 miles weekly at near my best aerobic efforts and that supplementary to this, by running at an easier effort as many miles as I possibly could. I also found that by alternating the length of the runs by running 10 miles one day and 20 the next, rather than by running 15 miles a day, I gained better results." -Arthur Lydiard

http://www.fitnesssports.com/lyd_clinic_guide/lydpg9.html

Lydiard advocated running about 100 miles a week in singles. Supplementary to that, he said to run as much as you have time and energy for at an easy aerobic effort, even if it is for just 15 minutes. Wetmore is the person that I can think of that advocated singles (I've heard that the University of Texas does also), however, they have other reason's to advocate singles.

You wouldn't happen to be Jesse A. from Connecticut would you?

Surprise! wrote:

You wouldn't happen to be Jesse A. from Connecticut would you?

If you're talking about me, then no, sorry! :-)

Lydiard may have talked about singles... but his runners most certainly ran doubles frequently.

Coe may have claimed to only run 50-60 mpw. But he never counted warmups, cooldowns, or jogging recoveries either.

Can you prove either of those statements?

I agree that Lydiard's runners ran twice a day. But what I am getting at is that you are going to have more benefit when running 16 miles straight than two runs of 8 miles.