Caffeine and Muscle Growth

[Anthony]

I heard Caffeine dont mix good with bodybuilding, is this true? i already pretty much cut all caffeine out of my diet but im just curious about this.

[Jazzy]

I read it's good for workout, because it's allow for greater intensity and In MD, I read that's caffeine raise the secretion of GH too!


It's good for increasing thermogenis, but, at some doses!


but too much isn't good too! :P

[emeric delczeg]

I heard Caffeine dont mix good with bodybuilding, is this true? i already pretty much cut all caffeine out of my diet but im just curious about this.

Not true, in a vitro study conducted at Washington State University on the effect of nutritional supplements on muscle-derived stem cells,it shows that caffein has proliferation effect. Long as you keep the mgs bettwen 75mg to 100mg befor training and 50mg one more time during the day. Take some other supplements 3 hours later that are lowering the cortisol levels elevated by the coffeine.

[Praetorian]

Any stimulant...caffeine included will raise cortisol levels. How high they go will be dependent on the individual as well as the dosage. A couple cups of coffee per day is fine...but just don't overdo it or you can run into trouble not just in regards to muscle catabolization but in the area of adrenal stress as well.
P

[YYZgeddylee]

there is evidence that caffiene effects blood sugar (-)

[Praetorian]

there is evidence that caffiene effects blood sugar (-)

Please post.
P

[juced_porkchop]

Any stimulant...caffeine included will raise cortisol levels. How high they go will be dependent on the individual as well as the dosage. A couple cups of coffee per day is fine...but just don't overdo it or you can run into trouble not just in regards to muscle catabolization but in the area of adrenal stress as well.
P

i agree. it would be very minimal with most peoples use (1-4 cupos of coffee or a couple caff pills a day)

I love my caff.

ill have my ASGT preWO and 1-2 cups of coffee later on and/or 1-2 cups of green tea. im growing just fine.
just make SURE your eating proporly (coffee might dull your hunger)

[YYZgeddylee]

Please post.
P

Damn this board, always keeping people accountable !

I think i first read it in Thomas Levy's 2001 book Optimal Nutrition Optimal Health.
He said caffiene works by releasing or mobilizing internal stores of
sugar directly into the bloodstream, typically at a very fast rate.
He also said it increases the size of the glucose spike when eaten
with food, maximizing fat storage. He said because of its glucose
mobilzing effects, it plays a role in chronically-elevated insulin levels.
When caffiene is ingested multiple times a day, it prevents insulin
levels from dropping back down to normal levels. As we know,
its very difficult to drop fat in the presence of chronically higher
levels of insulin. He didnt offer any direct citations to the research
that made him draw these conclusionss. I guess we'll call it a
hypothesis. It was probably based on research from the 1960's
that showed insulin resistance from caffiene intake.

It would be really easy to test yourself with a glucose meter
and regular measurements, measure a normal day with zero
caffiene ingestion, followed by measuring a day where caffiene
was ingested every few hours and see if there's a patern you
can draw a conclusion from.

Here's a paper from 2007. You can search some of the
references at the bottom to get a broader appreciation than
what this specific paper offers.


http://care.diabetesjournals.org/content/27/12/2990.full

without permission, with ommissions.

Effects of Coffee Consumption on Fasting Blood Glucose
and Insulin Concentrations Randomized controlled trials in
healthy volunteers

Rob M. van Dam, PHD1, Wilrike J. Pasman, PHD2 and Petra Verhoef, PHD34


Higher habitual coffee consumption was associated with higher insulin sensitivity (1) and a lower risk for type 2 diabetes (2–6) in diverse populations. In contrast, short-term metabolic studies showed that caffeine intake can acutely lower insulin sensitivity (7–9) and increase glucose concentrations (10–15). Randomized intervention studies are needed to examine whether tolerance to these acute effects develops after longer-term consumption (16). We therefore examined the effects of coffee and caffeine on fasting blood concentrations of glucose and insulin over 2–4 weeks in two crossover studies in healthy volunteers.

RESEARCH DESIGN AND METHODS
The studies were approved by the TNO Nutrition and Food Research Medical Ethics Committee, and all participants gave informed consent. The trials were originally designed to study the effects of coffee and caffeine on plasma concentrations of homocysteine, and the study designs have been reported in detail previously (17,18). Participants were regular coffee consumers (more than five cups/day) and did not have known diabetes.

The first study was a 4-week crossover study that compared the effects of regular paper-filtered coffee consumption with that of coffee abstinence. A total of 40 volunteers used 1 l of coffee (70 g coffee grounds) for 4 weeks and abstained from coffee for 4 weeks in random order. Fourteen participants did not complete the trial because of nausea and restlessness (n = 7), possible susceptibility to adverse effects of caffeine intake (n = 3), or reasons unrelated to treatment (n = 4). Thus, 26 participants were included in the analysis. The second study had a Latin-square design with three treatments given in random order for 2 weeks each: caffeine (a total of 870 mg in six capsules), regular paper-filtered coffee (52 g ground coffee/day in 0.9 l), and placebo (six capsules containing cellulose). Of the 54 volunteers, 6 subjects withdrew because of severe headaches (n = 2), study-related illness (n = 1), or reasons unrelated to treatment (n = 3). For the current analyses, we excluded participants because of missing blood samples (n = 1), not completing the whole caffeine intervention (n = 1), or who were clear outliers for an insulin concentration (n = 1). Thus, 45 subjects were included in the analysis. Caffeine-containing products (other than those provided) were prohibited during the entire trial. Venous blood samples were collected after an overnight fast. Plasma glucose concentrations were measured using the glucose hexokinase method. Serum insulin concentrations were measured using an immunoradiometric assay (Medgenix Biosource Diagnostics, Fleuris, Belgium).

In study 1, treatment responses were compared using paired t tests. In study 2, we tested for overall treatment effects using ANOVA. All reported P values were two sided, and P values <0.05 were considered statistically significant.

RESULTS

Study 1
Of the participants that completed the study, 62% were women, mean (±SD) age was 37 ± 12 years, and mean BMI was 23 ± 3 kg/m2. After 2 weeks, coffee consumption tended to lead to higher fasting glucose concentrations, but no appreciable effect was observed after 4 weeks (Table 1). Fasting insulin concentrations, measured only after 4 weeks, were higher after the coffee period than after the no coffee period (Table 1). Tests for carry-over effects did not indicate that these existed (insulin: P = 0.79; glucose: P = 0.27).

Study 2
Of the participants that completed the study, 56% were women, mean age was 40 ± 14 years, and mean BMI was 24 ± 3 kg/m2. Fasting glucose concentrations were similar after the caffeine, coffee, and placebo period (Table 1). Compared with the placebo period, fasting insulin concentrations tended to be higher after the coffee and caffeine periods (Table 1).

CONCLUSIONS
We found that high coffee consumption for 4 weeks increased fasting insulin concentrations compared with coffee abstinence. Consumption of somewhat weaker coffee and caffeine intake were nonsignificantly associated with higher fasting insulin concentrations. No substantial effects of coffee or caffeine on fasting glucose concentrations were observed.

The increased fasting insulin concentration after high coffee consumption in our study probably reflects decreased insulin sensitivity. In short-term metabolic studies, caffeine intake acutely lowered insulin sensitivity over 100–180 min (7–9). In a study of 5 days of caffeine intake, complete tolerance to the effects of caffeine on fasting glucose concentrations developed (19), but effects on norepinephrine and free fatty acid concentrations partly remained for the high-dose caffeine treatment. Thus, effects of high amounts of caffeine on catecholamines and free fatty acids may have contributed to a decrease in insulin sensitivity in our studies. However, we cannot completely exclude the possibility that the elevated insulin concentrations after coffee consumption were due to higher insulin secretion (20) or to reduced hepatic insulin clearance as a result of increased free fatty acid concentrations (21).

Our findings seem to be at variance with the inverse association between coffee consumption and risk for type 2 diabetes that has been observed in cohort studies (2–6). Several factors may contribute to this discrepancy. First, the results of cohort studies may reflect the effects of decades of regular coffee consumption, whereas the present study compared 2–4 weeks of coffee consumption with 2–4 weeks of coffee abstinence. Second, we cannot exclude the possibility that the rapid transition to high coffee consumption (equivalent to ∼13 conventional cups of coffee in study 1) in our studies had detrimental effects on insulin sensitivity. For example, experienced psychological stress may have lowered insulin sensitivity through increased stress hormone concentrations. Third, habitual coffee consumption may improve aspects of glucose metabolism that are not reflected in the outcome parameters of the present study (for example, postprandial glucose metabolism).

In conclusion, the present results indicate that tolerance to the adverse effects of high coffee consumption on insulin-glucose homeostasis does not develop within a 4-week period. This stresses that it is premature to advocate high coffee consumption as a means to lower risk for type 2 diabetes. Long-term trials of coffee consumption that include detailed measures of insulin sensitivity and glucose metabolism are warranted to elucidate the apparent discrepancy with studies that observed an inverse association between habitual coffee consumption and risk for type 2 diabetes.


References
1.↵Arnlov J, Vessby B, Riserus U: Coffee consumption and insulin sensitivity. JAMA 291:1199–1201, 2004 FREE Full Text
2.↵van Dam RM, Feskens EJ: Coffee consumption and risk of type 2 diabetes mellitus. Lancet 360:1477–1478, 2002 CrossRefMedlineWeb of Science
3.Rosengren A, Dotevall A, Wilhelmsen L, Thelle D, Johansson S: Coffee and incidence of diabetes in Swedish women: a prospective 18-year follow-up study. J Intern Med 255:89–95, 2004 CrossRefMedlineWeb of Science
4.Salazar-Martinez E, Willett WC, Ascherio A, Manson JE, Leitzmann MF, Stampfer MJ, Hu FB: Coffee consumption and risk for type 2 diabetes mellitus. Ann Intern Med 140:1–8, 2004 Abstract/FREE Full Text
5.Tuomilehto J, Hu G, Bidel S, Lindstrom J, Jousilahti P: Coffee consumption and risk of type 2 diabetes mellitus among middle-aged Finnish men and women. JAMA 291:1213–1219, 2004 Abstract/FREE Full Text
6.↵Carlsson S, Hammar N, Grill V, Kaprio J: Coffee consumption and risk of type 2 diabetes in Finnish twins (Letter). Int J Epidemiol 33:616–617, 2004
7.↵Greer F, Hudson R, Ross R, Graham T: Caffeine ingestion decreases glucose disposal during a hyperinsulinemic-euglycemic clamp in sedentary humans. Diabetes 50:2349–2354, 2001 Abstract/FREE Full Text
8.Keijzers GB, De Galan BE, Tack CJ, Smits P: Caffeine can decrease insulin sensitivity in humans. Diabetes Care 25:364–369, 2002
Abstract/FREE Full Text
9.↵Thong FS, Derave W, Kiens B, Graham TE, Urso B, Wojtaszewski JFP, Hansen BF, Richter EA: Caffeine-induced impairment of insulin action but not insulin signaling in human skeletal muscle is reduced by exercise. Diabetes 51:583–590, 2002 Abstract/FREE Full Text
10.↵Cheraskin E, Ringsdorf WM Jr, Setyaadmadja AT, Barrett RA: Effect of caffeine versus placebo supplementation on blood-glucose concentration. Lancet 1:1299–1300, 1967 Medline
11.Jankelson OM, Beaser SB, Howard FM, Mayer J: Effect of coffee on glucose tolerance and circulating insulin in men with maturity-onset diabetes. Lancet 1:527–529, 1967 Medline
12.Wachman A, Hattner RS, George B, Bernstein DS: Effects of decaffeinated and nondecaffeinated coffee ingestion on blood glucose and plasma radioimmunoreactive insulin responses to rapid intravenous infusion of glucose in normal man. Metabolism 19:539–546, 1970
CrossRefMedlineWeb of Science
13.Pizziol A, Tikhonoff V, Paleari CD, Russo E, Mazza A, Ginocchio G, Onesto C, Pavan L, Casiglia E, Pessina AC: Effects of caffeine on glucose tolerance: a placebo-controlled study. Eur J Clin Nutr 52:846–849, 1998
CrossRefMedlineWeb of Science
14.Mougios V, Ring S, Petridou A, Nikolaidis MG: Duration of coffee- and exercise-induced changes in the fatty acid profile of human serum. J Appl Physiol 94:476–484, 2003 Abstract/FREE Full Text
15.↵Lane JD, Barkauskas CE, Surwit RS, Feinglos MN: Caffeine impairs glucose metabolism in type 2 diabetes (Brief Report). Diabetes Care 27:2047–2048, 2004 FREE Full Text
16.↵Robertson D, Wade D, Workman R, Woosley RL, Oates JA: Tolerance to the humoral and hemodynamic effects of caffeine in man. J Clin Invest 67:1111–1117, 1981
17.↵Urgert R, van Vliet T, Zock PL, Katan MB: Heavy coffee consumption and plasma homocysteine: a randomized controlled trial in healthy volunteers. Am J Clin Nutr 72:1107–1110, 2000 Abstract/FREE Full Text
18.↵Verhoef P, Pasman WJ, Van Vliet T, Urgert R, Katan MB: Contribution of caffeine to the homocysteine-raising effect of coffee: a randomized controlled trial in humans. Am J Clin Nutr 76:1244–1248, 2002
Abstract/FREE Full Text
19.↵Denaro CP, Brown CR, Jacob P 3rd, Benowitz NL: Effects of caffeine with repeated dosing. Eur J Clin Pharmacol 40:273–278, 1991
CrossRefMedlineWeb of Science
20.↵Bruton JD, Lemmens R, Shi CL, Persson-Sjogren S, Westerblad H, Ahmed M, Pyne NJ, Frame M, Furman BL, Islam MS: Ryanodine receptors of pancreatic beta-cells mediate a distinct context-dependent signal for insulin secretion. FASEB J 17:301–303, 2003 Abstract/FREE Full Text
21.↵Wiesenthal SR, Sandhu H, McCall RH, Tchipashvili V, Yoshii H, Polonsky K, Shi ZQ, Lewis GF, Mari A, Giacca A: Free fatty acids impair hepatic insulin extraction in vivo. Diabetes 48:766–774, 1999 Abstract

[Praetorian]

Damn this board, always keeping people accountable !

I think i first read it in Thomas Levy's 2001 book Optimal Nutrition Optimal Health.
He said caffiene works by releasing or mobilizing internal stores of
sugar directly into the bloodstream, typically at a very fast rate.
He also said it increases the size of the glucose spike when eaten
with food, maximizing fat storage. He said because of its glucose
mobilzing effects, it plays a role in chronically-elevated insulin levels.
When caffiene is ingested multiple times a day, it prevents insulin
levels from dropping back down to normal levels. As we know,
its very difficult to drop fat in the presence of chronically higher
levels of insulin. He didnt offer any direct citations to the research
that made him draw these conclusionss. I guess we'll call it a
hypothesis. It was probably based on research from the 1960's
that showed insulin resistance from caffiene intake.

It would be really easy to test yourself with a glucose meter
and regular measurements, measure a normal day with zero
caffiene ingestion, followed by measuring a day where caffiene
was ingested every few hours and see if there's a patern you
can draw a conclusion from.

Here's a paper from 2007. You can search some of the
references at the bottom to get a broader appreciation than
what this specific paper offers.


http://care.diabetesjournals.org/content/27/12/2990.full

without permission, with ommissions.

Effects of Coffee Consumption on Fasting Blood Glucose
and Insulin Concentrations Randomized controlled trials in
healthy volunteers

Rob M. van Dam, PHD1, Wilrike J. Pasman, PHD2 and Petra Verhoef, PHD34


Higher habitual coffee consumption was associated with higher insulin sensitivity (1) and a lower risk for type 2 diabetes (2–6) in diverse populations. In contrast, short-term metabolic studies showed that caffeine intake can acutely lower insulin sensitivity (7–9) and increase glucose concentrations (10–15). Randomized intervention studies are needed to examine whether tolerance to these acute effects develops after longer-term consumption (16). We therefore examined the effects of coffee and caffeine on fasting blood concentrations of glucose and insulin over 2–4 weeks in two crossover studies in healthy volunteers.

RESEARCH DESIGN AND METHODS
The studies were approved by the TNO Nutrition and Food Research Medical Ethics Committee, and all participants gave informed consent. The trials were originally designed to study the effects of coffee and caffeine on plasma concentrations of homocysteine, and the study designs have been reported in detail previously (17,18). Participants were regular coffee consumers (more than five cups/day) and did not have known diabetes.

The first study was a 4-week crossover study that compared the effects of regular paper-filtered coffee consumption with that of coffee abstinence. A total of 40 volunteers used 1 l of coffee (70 g coffee grounds) for 4 weeks and abstained from coffee for 4 weeks in random order. Fourteen participants did not complete the trial because of nausea and restlessness (n = 7), possible susceptibility to adverse effects of caffeine intake (n = 3), or reasons unrelated to treatment (n = 4). Thus, 26 participants were included in the analysis. The second study had a Latin-square design with three treatments given in random order for 2 weeks each: caffeine (a total of 870 mg in six capsules), regular paper-filtered coffee (52 g ground coffee/day in 0.9 l), and placebo (six capsules containing cellulose). Of the 54 volunteers, 6 subjects withdrew because of severe headaches (n = 2), study-related illness (n = 1), or reasons unrelated to treatment (n = 3). For the current analyses, we excluded participants because of missing blood samples (n = 1), not completing the whole caffeine intervention (n = 1), or who were clear outliers for an insulin concentration (n = 1). Thus, 45 subjects were included in the analysis. Caffeine-containing products (other than those provided) were prohibited during the entire trial. Venous blood samples were collected after an overnight fast. Plasma glucose concentrations were measured using the glucose hexokinase method. Serum insulin concentrations were measured using an immunoradiometric assay (Medgenix Biosource Diagnostics, Fleuris, Belgium).

In study 1, treatment responses were compared using paired t tests. In study 2, we tested for overall treatment effects using ANOVA. All reported P values were two sided, and P values <0.05 were considered statistically significant.

RESULTS

Study 1
Of the participants that completed the study, 62% were women, mean (±SD) age was 37 ± 12 years, and mean BMI was 23 ± 3 kg/m2. After 2 weeks, coffee consumption tended to lead to higher fasting glucose concentrations, but no appreciable effect was observed after 4 weeks (Table 1). Fasting insulin concentrations, measured only after 4 weeks, were higher after the coffee period than after the no coffee period (Table 1). Tests for carry-over effects did not indicate that these existed (insulin: P = 0.79; glucose: P = 0.27).

Study 2
Of the participants that completed the study, 56% were women, mean age was 40 ± 14 years, and mean BMI was 24 ± 3 kg/m2. Fasting glucose concentrations were similar after the caffeine, coffee, and placebo period (Table 1). Compared with the placebo period, fasting insulin concentrations tended to be higher after the coffee and caffeine periods (Table 1).

CONCLUSIONS
We found that high coffee consumption for 4 weeks increased fasting insulin concentrations compared with coffee abstinence. Consumption of somewhat weaker coffee and caffeine intake were nonsignificantly associated with higher fasting insulin concentrations. No substantial effects of coffee or caffeine on fasting glucose concentrations were observed.

The increased fasting insulin concentration after high coffee consumption in our study probably reflects decreased insulin sensitivity. In short-term metabolic studies, caffeine intake acutely lowered insulin sensitivity over 100–180 min (7–9). In a study of 5 days of caffeine intake, complete tolerance to the effects of caffeine on fasting glucose concentrations developed (19), but effects on norepinephrine and free fatty acid concentrations partly remained for the high-dose caffeine treatment. Thus, effects of high amounts of caffeine on catecholamines and free fatty acids may have contributed to a decrease in insulin sensitivity in our studies. However, we cannot completely exclude the possibility that the elevated insulin concentrations after coffee consumption were due to higher insulin secretion (20) or to reduced hepatic insulin clearance as a result of increased free fatty acid concentrations (21).

Our findings seem to be at variance with the inverse association between coffee consumption and risk for type 2 diabetes that has been observed in cohort studies (2–6). Several factors may contribute to this discrepancy. First, the results of cohort studies may reflect the effects of decades of regular coffee consumption, whereas the present study compared 2–4 weeks of coffee consumption with 2–4 weeks of coffee abstinence. Second, we cannot exclude the possibility that the rapid transition to high coffee consumption (equivalent to ∼13 conventional cups of coffee in study 1) in our studies had detrimental effects on insulin sensitivity. For example, experienced psychological stress may have lowered insulin sensitivity through increased stress hormone concentrations. Third, habitual coffee consumption may improve aspects of glucose metabolism that are not reflected in the outcome parameters of the present study (for example, postprandial glucose metabolism).

In conclusion, the present results indicate that tolerance to the adverse effects of high coffee consumption on insulin-glucose homeostasis does not develop within a 4-week period. This stresses that it is premature to advocate high coffee consumption as a means to lower risk for type 2 diabetes. Long-term trials of coffee consumption that include detailed measures of insulin sensitivity and glucose metabolism are warranted to elucidate the apparent discrepancy with studies that observed an inverse association between habitual coffee consumption and risk for type 2 diabetes.


References
1.↵Arnlov J, Vessby B, Riserus U: Coffee consumption and insulin sensitivity. JAMA 291:1199–1201, 2004 FREE Full Text
2.↵van Dam RM, Feskens EJ: Coffee consumption and risk of type 2 diabetes mellitus. Lancet 360:1477–1478, 2002 CrossRefMedlineWeb of Science
3.Rosengren A, Dotevall A, Wilhelmsen L, Thelle D, Johansson S: Coffee and incidence of diabetes in Swedish women: a prospective 18-year follow-up study. J Intern Med 255:89–95, 2004 CrossRefMedlineWeb of Science
4.Salazar-Martinez E, Willett WC, Ascherio A, Manson JE, Leitzmann MF, Stampfer MJ, Hu FB: Coffee consumption and risk for type 2 diabetes mellitus. Ann Intern Med 140:1–8, 2004 Abstract/FREE Full Text
5.Tuomilehto J, Hu G, Bidel S, Lindstrom J, Jousilahti P: Coffee consumption and risk of type 2 diabetes mellitus among middle-aged Finnish men and women. JAMA 291:1213–1219, 2004 Abstract/FREE Full Text
6.↵Carlsson S, Hammar N, Grill V, Kaprio J: Coffee consumption and risk of type 2 diabetes in Finnish twins (Letter). Int J Epidemiol 33:616–617, 2004
7.↵Greer F, Hudson R, Ross R, Graham T: Caffeine ingestion decreases glucose disposal during a hyperinsulinemic-euglycemic clamp in sedentary humans. Diabetes 50:2349–2354, 2001 Abstract/FREE Full Text
8.Keijzers GB, De Galan BE, Tack CJ, Smits P: Caffeine can decrease insulin sensitivity in humans. Diabetes Care 25:364–369, 2002
Abstract/FREE Full Text
9.↵Thong FS, Derave W, Kiens B, Graham TE, Urso B, Wojtaszewski JFP, Hansen BF, Richter EA: Caffeine-induced impairment of insulin action but not insulin signaling in human skeletal muscle is reduced by exercise. Diabetes 51:583–590, 2002 Abstract/FREE Full Text
10.↵Cheraskin E, Ringsdorf WM Jr, Setyaadmadja AT, Barrett RA: Effect of caffeine versus placebo supplementation on blood-glucose concentration. Lancet 1:1299–1300, 1967 Medline
11.Jankelson OM, Beaser SB, Howard FM, Mayer J: Effect of coffee on glucose tolerance and circulating insulin in men with maturity-onset diabetes. Lancet 1:527–529, 1967 Medline
12.Wachman A, Hattner RS, George B, Bernstein DS: Effects of decaffeinated and nondecaffeinated coffee ingestion on blood glucose and plasma radioimmunoreactive insulin responses to rapid intravenous infusion of glucose in normal man. Metabolism 19:539–546, 1970
CrossRefMedlineWeb of Science
13.Pizziol A, Tikhonoff V, Paleari CD, Russo E, Mazza A, Ginocchio G, Onesto C, Pavan L, Casiglia E, Pessina AC: Effects of caffeine on glucose tolerance: a placebo-controlled study. Eur J Clin Nutr 52:846–849, 1998
CrossRefMedlineWeb of Science
14.Mougios V, Ring S, Petridou A, Nikolaidis MG: Duration of coffee- and exercise-induced changes in the fatty acid profile of human serum. J Appl Physiol 94:476–484, 2003 Abstract/FREE Full Text
15.↵Lane JD, Barkauskas CE, Surwit RS, Feinglos MN: Caffeine impairs glucose metabolism in type 2 diabetes (Brief Report). Diabetes Care 27:2047–2048, 2004 FREE Full Text
16.↵Robertson D, Wade D, Workman R, Woosley RL, Oates JA: Tolerance to the humoral and hemodynamic effects of caffeine in man. J Clin Invest 67:1111–1117, 1981
17.↵Urgert R, van Vliet T, Zock PL, Katan MB: Heavy coffee consumption and plasma homocysteine: a randomized controlled trial in healthy volunteers. Am J Clin Nutr 72:1107–1110, 2000 Abstract/FREE Full Text
18.↵Verhoef P, Pasman WJ, Van Vliet T, Urgert R, Katan MB: Contribution of caffeine to the homocysteine-raising effect of coffee: a randomized controlled trial in humans. Am J Clin Nutr 76:1244–1248, 2002
Abstract/FREE Full Text
19.↵Denaro CP, Brown CR, Jacob P 3rd, Benowitz NL: Effects of caffeine with repeated dosing. Eur J Clin Pharmacol 40:273–278, 1991
CrossRefMedlineWeb of Science
20.↵Bruton JD, Lemmens R, Shi CL, Persson-Sjogren S, Westerblad H, Ahmed M, Pyne NJ, Frame M, Furman BL, Islam MS: Ryanodine receptors of pancreatic beta-cells mediate a distinct context-dependent signal for insulin secretion. FASEB J 17:301–303, 2003 Abstract/FREE Full Text
21.↵Wiesenthal SR, Sandhu H, McCall RH, Tchipashvili V, Yoshii H, Polonsky K, Shi ZQ, Lewis GF, Mari A, Giacca A: Free fatty acids impair hepatic insulin extraction in vivo. Diabetes 48:766–774, 1999 Abstract

The studies parameters are over a 4 week time frame and are inconclusive as to whether or not the level of fasting insulin was due to decreased insulin sensitivity. Thus one cannot say that caffeine ingested in the short term will affect insulin levels at all...which is what most are concerned about.
Thanks for posting.
P

[ironwill]

Not true, in a vitro study conducted at Washington State University on the effect of nutritional supplements on muscle-derived stem cells,it shows that caffein has proliferation effect. Long as you keep the mgs bettwen 75mg to 100mg befor training and 50mg one more time during the day. Take some other supplements 3 hours later that are lowering the cortisol levels elevated by the coffeine.

Hello Emeric, ive seen you at promuscle a lot....If this is the Real Emeric, it would be good of you to post up in the intro section so folks know who you are, and that you have some great advices for those wanting to learn a tonne...
:greet