A few studies suggest these may be pretty good for endurance exercise... anyone used them?

Effects of phosphate loading on 2,3-diphosphoglycerate and maximal oxygen uptake.

Cade R, Conte M, Zauner C, Mars D, Peterson J, Lunne D, Hommen N, Packer D.

Increased concentration of red blood cell 2,3-diphosphoglycerate (RBC 2,3-DPG) shifts the hemoglobin-oxygen dissociation curve to the right, thus theoretically allowing better oxygenation of tissues. To determine whether such a shift is physiologically significant, we investigated the effects of oral phosphate loading on several parameters including plasma phosphate concentration, RBC 2,3-DPG, hematocrit and hemoglobin concentration, maximal oxygen uptake (VO2max), and degree of lactic acidemia in 10 well-trained distance runners. After control determinations were made, either a phosphate load or a placebo was given for 3 d before the athlete was restudied. A placebo and two phosphate-loading studies were performed at weekly intervals, followed by 2 wk of rest and another post-intervention control study. Blood samples for control values were drawn before and after a standard warm-up period, after treadmill exercise at a 10% grade, and at the completion of the VO2 determination. After oral phosphate loading there was a significant increase in serum phosphate and RBC 2,3-DPG. Maximal oxygen uptake was significantly increased and correlated with the rise in RBC 2,3-DPG (r = 0.81). The increase in blood lactate after exercise on the 10% grade was attenuated during sessions which followed phosphate loading.

abstract

Effects of phosphate loading on oxygen uptake, ventilatory anaerobic threshold, and run performance.
Kreider RB, Miller GW, Williams MH, Somma CT, Nasser TA.

Department of Health, Physical Education and Recreation, Human Performance Laboratory, Old Dominion University, Norfolk, VA 23529-0196.

Seven male competitive runners (VO2max 73.9 +/- 6.3 ml.kg-1.min-1) participated in a two-session, placebo, double-blind study to determine the effects of phosphate loading on oxygen uptake, ventilatory anaerobic threshold, and 5-mile run performance. Subjects ingested 1000 mg of tribasic sodium phosphate or a placebo four times daily for 6 d. A maximal running stress test or a 5-mile performance run was performed randomly on either the 3rd or the 6th d. Test sessions were separated by a 2-wk washout period and repeated with alternating phosphate and placebo regimens. Venous blood samples were collected prior to and following each max and run session. Results revealed that placebo resting serum phosphate levels were mildly elevated and that phosphate loading significantly increased resting and post-exercise serum phosphate values. Resting and post-exercise 2,3-diphosphoglycerate values were decreased while hemoglobin values were elevated with phosphate ingestion. Phosphate loading significantly increased maximal oxygen uptake from 4.77 +/- 0.29 to 5.18 +/- 0.25 l.min-1 and ventilatory anaerobic threshold from 3.74 +/- 0.28 to 4.18 +/- 0.14 l.min-1. Five-mile run times were nonsignificantly different between placebo and phosphate sessions. However, mean performance run oxygen uptake was significantly lower (3.87 +/- 0.3 to 3.80 +/- 0.3 l.min-1) with phosphate ingestion. Data demonstrate that maximal and run performance were influenced by elevations in serum phosphate eliciting an increased maximal oxygen uptake, ventilatory anaerobic threshold, and variable effects on 5-mile run performance. These adaptations occurred without observable increases in red cell 2,3-diphosphoglycerate.

abstract

Effects of phosphate loading on metabolic and myocardial responses to maximal and endurance exercise.

Kreider RB, Miller GW, Schenck D, Cortes CW, Miriel V, Somma CT, Rowland P, Turner C, Hill D.

Dept. of HPER, Old Dominion University, Norfolk, VA 23529-0196.

Six trained male cyclists and triathletes participated in a double blind study to determine the effects of phosphate loading on maximal and endurance exercise performance. Subjects ingested either 1 gm of tribasic sodium phosphate or a glucose placebo four times daily for 3 days prior to performing either an incremental maximal cycling test or a simulated 40-km time trial on a computerized race simulator. They continued the supplementation protocol for an additional day and then performed the remaining maximal or performance exercise test. Subjects observed a 17-day washout period between testing sessions and repeated the experiment with the alternate supplement regimen in identical fashion. Metabolic data were collected at 15-sec intervals while venous blood samples and 2D-echocardiographic data were collected during each stage of exercise during the maximal exercise test and at 8-km intervals during the 40-km time trial. Results indicate that phosphate loading attenuated anaerobic threshold, increased myocardial ejection fraction and fractional shortening, increased maximal oxidative capacity, and enhanced endurance performance in competitive cyclists and triathletes.

abstract

Would IP6 (Inositol Hexaphosphate) come under this category?

I've used it and still have quite a lot left in the cupboard.... pain in the arse to supplement with as it needs taking away from foods.

What Is It?
IP6 is simply inositol hexaphosphate where 6 phosphate groups are bound to a 6 carbon skeleton (the backbone in organic chem.). IP6 is a novel phosphate donor, which reduces the GI distress of traditional mineral phosphate loading. As far as IP6 is concerned, research has shown that IP6 a compound ingested is actually IP3 as the bio-active (and what's in the cell). This means 3 phosphates are "freed" and hence donated. Phosphate "donation" would theoretically lead to enhanced athletic performance as mentioned below. IP6 is one of those exciting compounds if you read on the longevity sites and far more beneficial than just as an ergogenic. AMP (adenosine monophosphate) in the mitochondria of the cell requires one more phosphate to make ADP, and yet another to produce ATP. ATP is your basic energy molecule and perhaps the most essential in the idea of ergogenics and athletic performance. Phosphate maybe one of, if not the most important mineral constituent required for cellular activity due to its biological interactions with metabolic intermediates and energy producing compounds. Changes in cellular phosphate levels have been linked to enhanced exercise capacity time and time again. Supplementation is a proven method to achieve this guaranteed performance effect.

How Does It Work?
There are many possible Mechanisms proposed for the proven influence of phosphate including:

1. Phosphate-stimulated glycolysis (enhanced energy production capacity)[19]
2. Increased red blood cell 2,3-DPG levels (Enhancing oxygen delivery to working muscles)[20]
3. Enhanced creatine phosphate synthesis (increased creatine stores)[21].


What Evidence For Performance Effect?
There are many studies proving the performance enhancement of phosphate loading for athletes. Kreider et al. (1992) assessed the influence of 1000mg of phosphate 4 times a day for 3 days or a maltodextrin placebo. The results backed many other studies and showed that phosphate loading could enhance maximal exercise performance (40km time trial).

...

That IP6 looks like a phosphate salt to me... what effects did you get off it?

It was an impulse buy a while ago, I needed to spend another couple of pounds to qualify for free delivery lol!

I didn't read up on it fully and later found out it's a very potent at chelating minerals, so needs to be taken away from food on an empty stomach. It's a pain to take so never really bothered with it... it's still in the cupboard now. Thinking of starting using pre-workout, supposed to be very good stuff.

Man clout has IP6 in it. Looks like a good creatine supplement.

Serving Size: 1 scoop (10.5g)
Servings per Container: 50
Amount Per Serving
OROTINE™ (Tricreatine Orotate)
3,000mg +
N-Acetyl-Cysteine
2,000mg +
Beta-Alanine
1,600 mg +
MAG-MALATE™ (Magnesium Malate)
560.5mg +
Orotic Acid
500mg +
Vinpocetine
8mg +
PHOSPHA-DRIVE™

Magnesium Phosphate, Dibasic
351.5mg +
Potassium Phosphate, Dibasic
220mg +
Sodium Phosphate, Monobasic
216mg +

Bioactive #5 Inositol HexaPhosphate (IP6)

What Is It?
IP6 is simply inositol hexaphosphate where 6 phosphate groups are bound to a 6 carbon skeleton (the backbone in organic chem.). IP6 is a novel phosphate donor, which reduces the GI distress of traditional mineral phosphate loading. As far as IP6 is concerned, research has shown that IP6 a compound ingested is actually IP3 as the bio-active (and what's in the cell). This means 3 phosphates are "freed" and hence donated. Phosphate "donation" would theoretically lead to enhanced athletic performance as mentioned below. IP6 is one of those exciting compounds if you read on the longevity sites and far more beneficial than just as an ergogenic. AMP (adenosine monophosphate) in the mitochondria of the cell requires one more phosphate to make ADP, and yet another to produce ATP. ATP is your basic energy molecule and perhaps the most essential in the idea of ergogenics and athletic performance. Phosphate maybe one of, if not the most important mineral constituent required for cellular activity due to its biological interactions with metabolic intermediates and energy producing compounds. Changes in cellular phosphate levels have been linked to enhanced exercise capacity time and time again. Supplementation is a proven method to achieve this guaranteed performance effect.

How Does It Work?
There are many possible Mechanisms proposed for the proven influence of phosphate including:

1. Phosphate-stimulated glycolysis (enhanced energy production capacity)[19]
2. Increased red blood cell 2,3-DPG levels (Enhancing oxygen delivery to working muscles)[20]
3. Enhanced creatine phosphate synthesis (increased creatine stores)[21].

Therefore, it is easy to see how phosphate addition can further extend the influence of Clout™ as the ultimate creatine and performance enhancer.

What Evidence For Performance Effect?
There are many studies proving the performance enhancement of phosphate loading for athletes. Kreider et al. (1992) assessed the influence of 1000mg of phosphate 4 times a day for 3 days or a maltodextrin placebo. The results backed many other studies and showed that phosphate loading could enhance maximal exercise performance (40km time trial).

IP6 = phytic acid. Most of us soak grains to avoid this

cleaver wrote:IP6 = phytic acid. Most of us soak grains to avoid this

I thought I'd seen inositol hexaphosphate somewhere! Surely something you'd want to avoid supplementing with, might be all right if you took it away from food though.

Exactly... it's a pain in the arse to supplement with, not worth the hassle.