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PubMed1988

Effects of imidazole-2-hydroxibenzoate on glycosaminoglycan and albumin urinary excretion in type 1 diabetic patients.

The effect of imidazole-2-hydroxibenzoate on urinary excretion rates of glycosaminoglycans and albumin in 22 insulin-dependent diabetics with albumin excretion rates under 300 mg/day was evaluated in a 165-day double blind crossover study. Unlike placebo, the drug reduced glycosaminoglycan and albumin excretion rates significantly after 40 and 60 days of treatment, and the effects were significantly intercorrelated. Moreover, a parallel reduction in urinary excretion of N-acetyl-beta-D-glucosaminidase was also observed. These pharmacological effects may have a positive impact on the subsequent natural history of diabetic nephropathy.

Acetylglucosaminidase↗
PubMed1999

Slowing the titration rate of tramadol HCl reduces the incidence of discontinuation due to nausea and/or vomiting: a double-blind randomized trial.

BACKGROUND: Ultram [tramadol hydrochloride (HCl)] is a centrally acting analgesic that is widely prescribed for the treatment of moderate to moderately severe chronic pain. Although tramadol is generally well tolerated, some patients discontinue use early in the course of treatment because of nausea and vomiting. OBJECTIVE: To investigate the effect of three initial titration rates of tramadol HCl on the incidence of discontinuation due to nausea and/or vomiting in patients who previously did not tolerate tramadol HCl. METHOD: A multicentre, outpatient, randomized double-blind study was conducted, comprised of two phases: a 14-day open-label run-in phase and a 28-day double-blind phase. In the run-in phase the dose of tramadol was titrated over 4 days to the target of 200 mg/day. Patients who discontinued tramadol HCl due to nausea and/or vomiting in the open-label phase were eligible to enter the 28-day double-blind phase after a 10-day wash-out. Patients were randomized to one of three groups using a 10-, 16- or a 13-day titration schedule in order to achieve a target dosage of either 200 mg/day (10- and 16-day titration groups) or 150 mg/day (13-day titration group). The number of discontinuations due to nausea and/or vomiting in each group were compared. RESULTS: Significantly fewer patients (22%) discontinued because of nausea and/or vomiting in the 13- and 16-day titration groups compared to the 10-day group (P=0.008 and P=0.006, respectively). The time to discontinuation was also significantly delayed in the 13- and 16-day groups compared to the 10-day group (P=0.006 and P=0.007, respectively). The outcome of the 13-day titration to 150 mg/day was essentially the same as that of the 16-day titration to 200 mg/day, suggesting that this is a true rate effect rather than being dose related. CONCLUSION: This study demonstrated that a slower titration rate of tramadol HCl improves tolerability in patients who previously discontinued therapy due to nausea and/or vomiting. This study also demonstrates that the rate of titration of tramadol HCl rather than the target dose is the major determinant of tolerability.

Adult↗
PubMed1983

Verapamil for unstable angina at rest: a short-term randomized, double-blind study.

To assess the efficacy of verapamil in individuals with unstable angina at rest, 11 patients (five men and six women, average age 55 years) with recurrent chest pain at rest and transient ST segment deviation (elevation or depression greater than or equal to 0.1 mV) on continuous ECG monitoring were enrolled in a 3-day double-blind, randomized study. The day before randomization (day 1), all received single-blind placebo. On day 2 they were randomized to placebo (n = 6) or verapamil, 320 mg per day (n = 5). On placebo, the number of chest pains (day 1, 2.8 +/- 2.1; day 2, 2.2 +/- 2.5; NS), nitroglycerin used (day 1, 2.7 +/- 4.4 tablets; day 2, 2.2 +/- 3.5 tablets; NS), and ST segment deviations (day 1, 8.5 +/- 5.9; day 2, 5.3 +/- 7.1; NS) did not change. On verapamil, the number of chest pains (day 1, 5.4 +/- 2.2; day 2, 1.6 +/- 2.1; p less than 0.01), nitroglycerin used (day 1, 5.0 +/- 4.5 tablets; day 2, 1.6 +/- 2.6 tablets; p = 0.057), and ST segment deviations (day 1, 12.6 +/- 4.7; day 2, 6.2 +/- 6.2; p less than 0.05) fell. Since five of six placebo patients had frequent chest pain and ST segment deviations on day 2, they were changed blindly to verapamil, 320 mg per day. Of the five verapamil patients, three had no chest pain or ST segment deviations on day 2, but two had continued chest pain and ST segment deviations and were increased blindly to 480 mg verapamil per day. Of the eight patients given verapamil (320 mg per day) on day 3, five had chest pain or ST segment deviations and were increased blindly to 480 mg verapamil per day on day 4. Of the seven who received 480 mg verapamil per day on day 4, three had chest pain and ST segment deviations similar in frequency to that occurring on day 1. Thus in patients with unstable angina at rest, verapamil exerts an initial beneficial effect, but in some individuals this salutary influence is not sustained.

Adult↗
PubMed1989

The effects of flurbiprofen, aspirin, cimetidine, and antacids on the gastric and duodenal mucosa of normal volunteers. An endoscopic and photographic study.

This 7-day, single blind, randomized endoscopic tolerance study compared daily doses of 100, 150 and 200 mg flurbiprofen with 2600 mg aspirin. After seven days the flurbiprofen 100 and 150 mg groups had significantly less gastric irritation than the flurbiprofen 200 mg and aspirin groups. Flurbiprofen showed a linear dose-response relationship with respect to gastric injury and serum drug levels. Four subjects each on aspirin and flurbiprofen with the most severe injuries continued on their medications plus cimetidine and antacids for four more weeks. Both drug groups showed clinical improvement in the gastroduodenal area. In conclusion, flurbiprofen and aspirin therapy can be tolerated in the presence of gastroduodenal irritation by concomitantly administering cimetidine and antacids.

Adult↗
PubMed1985

Effect of short and long photoperiods on pineal N-acetyltransferase rhythm and on growth of testes and brown adipose tissue in developing rats.

The effect of photoperiod on the rhythm in pineal N-acetyltransferase activity and on the growth of testes and of brown adipose tissue was studied in infant rats at the age of 5-15 days. After exposure to light at night, high N-acetyltransferase activity declined in 6-, 7-, and 8-day-old intact rats, but not in 5-day-old intact rats or in 8-day-old blinded rats. Hence, light might penetrate under closed eyelids and might be perceived by retinal photoreceptors in rats older than 6 days. In 15-day-old animals, the amplitude of the N-acetyltransferase rhythm was ten times higher than in 5-day-old rats. The pattern of the N-acetyltransferase rhythm, namely the duration of elevated nocturnal activity, was different under long and short photoperiod at least 1 week before opening of eyes. Photoperiod affected the growth of testes and of interscapular brown adipose tissue already in the preweaning period. In 15-day-old rats, immediately after opening of eyes, the weight of testes was significantly higher and the weight of brown fat lower under long than under short photoperiod. Photoperiodic regulation thus occurs before rats open their eyelids.

Acetyltransferases↗
PubMed1981

Zimelidine vs maprotiline in depressed outpatients. A preliminary report.

Outpatients with endogenous depression diagnosed according to the research diagnostic criteria of Feighner et al. were randomly referred to treatment with zimelidine (100 mg b.i.d., group Z) or maprotiline (75 mg b.i.d., group M). Patients who did not respond to treatment by days 28 were crossed over to the other drug. This preliminary report comprises results up to day 28 and includes antidepressive effect as rated by CPRS and globally, side effects, clinical chemistry and ECG. Ratings were double-blind at days 0, 7, 14 and 28, and a washout period of 4--7 days preceeded the trial. Group Z includes 27 and group M 28 patients with equal distribution of sex, age, duration of present episode, initial severity, etiology and previous course. There were 11 dropouts in group M and 5 in group Z due to side effects or treatment failure. On the other hand, 8 patients in group Z had to cross over to the other drug versus 2 in group M. According to the total CPRS score and the global score the antidepressive effect was somewhat better in group Z at 2 weeks but similar at 1 and 4 weeks. Group Z is less sedative but still seems to have a better anti-anxiety effect. Side effects were on a low level. There was a greater number of patients in group Z who complained of nausea, vomiting, loose stools, sleep disorder and sweating, and in group M dry mouth, drowsiness, dizziness and accomodation difficulties. Chemical analyses and ECG showed slight and inconsistent changes.

Adult↗
PubMed1991

A double-blind, placebo-controlled, 6-day evaluation of two doses of misoprostol in gastroduodenal mucosal protection against damage from aspirin and effect on bowel habits.

Ninety-one normal, healthy volunteers participated in a single-center, double-blind, placebo-controlled, randomized, parallel group study: 1) to compare the prostaglandin E1 analog, misoprostol, given at a dose of 200 micrograms bid, with the recommended dose of 200 micrograms qid in protecting the gastroduodenal mucosa against injury due to anti-inflammatory doses of aspirin (3900 mg/day); and 2) to determine whether the reduced dose was associated with a lesser incidence of gastrointestinal (GI) side effects, particularly diarrhea. All subjects received 975 mg of aspirin qid with meals and at bedtime. They were concurrently administered either misoprostol 200 micrograms qid, misoprostol 200 micrograms bid and placebo bid, or placebo qid. All subjects were endoscopically normal at the onset of the study and were re-endoscoped on the morning of the 7th day of therapy, 2 h after the morning dose of medications. Gastric and duodenal mucosa were assessed separately on a 0-7 scale which gave a greater weight to erosions than to hemorrhages. GI symptoms, especially bowel habits, were assessed by means of diary cards. Subjects in both misoprostol groups had significantly less gastric and duodenal mucosal injury than subjects who received placebo (p less than 0.007 for each pairwise comparison). There was no statistically significant difference between the two misoprostol groups (p less than 0.093). Subjects in the misoprostol 200 micrograms qid group had significantly more loose and watery bowel movements than the subjects in the misoprostol 200 micrograms bid group (p less than 0.013), whereas there were no significant differences in bowel habits between the misoprostol 200 micrograms bid and placebo groups (p less than 0.122). More subjects in the misoprostol 200 micrograms qid group reported abdominal pain, loose stools, watery stools, flatulence, dyspepsia, and nausea than in the misoprostol 200 micrograms bid and placebo groups. In conclusion, the adverse events in the misoprostol 200 micrograms bid group were not significantly different from those in the placebo group, and were significantly better than in the misoprostol 200 micrograms qid group. The lower dose retained mucosal protective activity that was statistically indistinguishable from that of misoprostol 200 micrograms qid.

Adult↗
PubMedDate not supplied

Betamethasone valerate in foam vehicle is effective with both daily and twice a day dosing: a single-blind, open-label study in the treatment of scalp psoriasis.

BACKGROUND: Psoriasis is a chronic relapsing skin disorder that affects about 2% of the U.S. population and involves the scalp approximately 50% of the time. Topical corticosteroids, including betamethasone valerate, have been used effectively in the treatment of corticosteroid-responsive dermatoses of the skin and scalp. Betamethasone valerate (BMV) in foam vehicle (Luxiq) is designed to improve patient compliance with topical therapy. Superior efficacy over a BMV lotion preparation has been demonstrated with twice-daily use. Even greater compliance would be expected if the drug is effective with once-daily application. PURPOSE: To compare the efficacy of the betamethasone valerate foam (Luxiq) in the treatment of scalp psoriasis following once-daily versus twice-daily dosing. METHODS: Seventy-nine patients with moderate to severe scalp psoriasis from seven centers were enrolled and treated with BMV foam either once a day or twice a day for four weeks. The physician-grader was blinded to the treatment regimen, and the subjects were randomly assigned to either once-daily or twice-daily dosing in a 1:1 ratio. RESULTS: The signs of psoriasis (plaque thickness, scaling, and erythema) were assessed before and after treatment. The investigator's and the patients' global assessments were also evaluated. The composite score improved from 7.7 +/- 2.1 to 3.0 +/- 2.2 with twice-a-day use and from 8.1 +/- 2.2 to 3.9 +/- 2.8 with once-daily use (p > 0.05 for the difference between groups). DISCUSSION: BMV foam is effective for scalp psoriasis with both once-a-day and twice-a-day use. This feature of the BMV foam is encouraging for expected improvement in clinical use.

Administration, Topical↗
PubMed1987

Phase shifts in the circadian activity rhythm induced by triazolam are not mediated by the eyes or the pineal gland in the hamster.

A single injection of the benzodiazepine triazolam, which is though to act by potentiating the effects of the neurotransmitter gamma-aminobutyric acid (GABA), can induce permanent phase shifts in the circadian rhythm of locomotor activity of hamsters. Occurrence of GABA immunoreactivity and benzodiazepine receptors in the retina, which contains photoreceptors that relay synchronizing light-dark information to the mammalian circadian system, raises the possibility that triazolam may influence circadian rhythmicity via an action on the retina. However, the phase shifting effects of triazolam on the activity rhythm were unaffected by blinding: the direction and the magnitude of the phase shifts were similar in blind hamsters and in sighted hamsters maintained in constant darkness. Furthermore, no change in response to triazolam was observed in hamsters studied through 84 days after blinding. In addition, benzodiazepine binding sites have been found in the mammalian pineal gland, which has also been implicated in circadian rhythmicity. Therefore, its possible involvement in mediating the phase advancing effects of triazolam on the circadian clock has also been tested: the response was similar in blind and blind-pinealectomized animals. These results indicate that the effects of triazolam on the circadian clock are not mediated by the eyes or the pineal gland.

Animals↗
PubMed1984

Etodolac, aspirin, and gastrointestinal microbleeding.

The effects of etodolac, a new nonsteroidal anti-inflammatory drug, on gastrointestinal (GI) microbleeding were quantitatively assessed in two studies in healthy adult men. The first was a two-group, open-label, parallel comparison of etodolac, 600 mg/day, aspirin, 2600 mg/day, and placebo in 20 subjects; the second was a four-group, double-blind, parallel comparison of etodolac, 600, 800, and 1200 mg/day, aspirin, 2600 mg/day, and placebo in 41 subjects. Subjects in both studies received a single-blind placebo on days 1 through 7, either etodolac or aspirin on days 8 through 14, and a single-blind placebo on days 15 through 19. GI blood loss (milliliters per day) was estimated by the radiolabeled (51Cr) erythrocyte method and was based on daily radioactivity counts of stool specimens and regression-estimated daily blood radioactivity. Etodolac, 600 mg/day, induced no significant GI blood loss at any time during the experiments, nor was there significant blood loss after 800 and 1200 mg/day in experiment 2. Blood loss was noted after aspirin in both.

Acetates↗
PubMed2003

[Successful reduction of the SCORAD score by a short-time teaching method using a simplified skin model in children with atopic eczema in a 6-week comparison].

BACKGROUND: In order to achieve a long-term stabilizing effect on the clinical condition of the skin of patients with atopic eczema, it is imperative to perform consistent topical skincare. Because of time pressures during normal office visits, it is impossible to thoroughly counsel patients who suffer from atopic eczema. We performed a randomized and prospective comparative study to evaluate the outpatient effectiveness of a short-time but impressive teaching and counselling method using the skin model developed by Kardorff and Schnelle-Parker. PATIENTS AND METHODS: Thirty outpatients between 3 and 6 years old with moderate or severe atopic eczema were evaluated. Half of the patients were trained by an active, 10-min demonstration with the skin model on day 0 and day 14. Patients in the control group received verbal instructions of the same duration, as in routine dermatological practice. The SCORAD score was measured blindly on days 0, 14 and 42. RESULTS: After 42 days, the SCORAD score of the patients taught by the use of the Kardorff-Schnelle-Parker skin model was significantly reduced compared to the control group (P < 0.006). CONCLUSIONS: By counselling atopic children, even of preschool age, with the easily understandable skin model incorporating the sense of touch, better compliance concerning regular skincare can be achieved. We expect positive effects in the long-term management of atopic eczema.

Child↗
PubMed1992

Dose ranging study of lansoprazole, a new proton pump inhibitor, in patients with high gastric acid secretion.

The effects of single doses and of 7 days of lansoprazole 10, 20 and 30 mg PO versus placebo on gastric acid secretion have been evaluated in 8 patients with high gastric acid secretion. The double blind crossover period was followed by a simple blind 7 days on placebo to detect any rebound phenomenon. After the first dose lansoprazole did not modify basal acid output (BAO) but it significantly and dose dependently inhibited peak acid output (PAO) and increased the time during which nocturnal intragastric pH was greater than 3. After 7 days of treatment the same significant, dose-dependent suppression of gastric acid was found, but BAO was also blocked. One week after cessation of lansoprazole administration no rebound increase in gastric acid-secretion was observed. The plasma gastrin concentration remained unchanged throughout the study.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1985

Parenteral aspirin for pain relief in day-case dental anaesthesia. A randomised double blind placebo controlled trial.

Forty patients undergoing day-case anaesthesia for surgical extraction of third molar teeth received either lysine acetylsalicylate 1.8 g in 10 ml of saline intravenously or a placebo injection of 10 ml of saline intravenously just prior to induction of anaesthesia. Lysine acetylsalicylate was associated with a significantly more satisfactory postoperative recovery overall. However, there was no significant difference in mean pain scores between the two treatment groups at 1, 6, 12 or 24 hours following administration. Both treatment groups self administered additional oral analgesics to the same extent during the first 24 hours following surgery.

Adolescent↗
PubMed2005

A double-blind, placebo- and positive-internal-controlled (alprazolam) investigation of the cognitive and psychomotor profile of pregabalin in healthy volunteers.

RATIONALE: Pregabalin potently and selectively binds to the alpha(2)-delta subunit of voltage-dependent calcium channels, reducing calcium influx and modulating release of downstream excitatory neurotransmitters, such as glutamate. Pregabalin has demonstrated robust efficacy for several disease states, but its neuropharmacology is still being elucidated. OBJECTIVE: This study was conducted to evaluate the cognitive and psychomotor effects of oral pregabalin (150 mg t.i.d.) using alprazolam (1 mg t.i.d.) as a positive internal control and placebo. METHODS: Twenty-four healthy volunteers were randomised to a double-blind, three-way crossover study. Each period consisted of 3-day double-blind treatment followed by 1 day of single-blind placebo. Psychometrics included tests of Choice Reaction Time (CRT), CNS arousal (Critical Flicker Fusion, CFF), vigilance (Rapid Visual Information Processing, RVIP), serial memory scanning (Sternberg Short-Term Memory Scanning Test, STM), divided attention (Compensatory Tracking Task, CTT), Brake Reaction Time (BRT) in an on-the-road vehicle, and subjective Line Analogue Rating Scales (LARS) for sedation. RESULTS: Pregabalin showed no significant effects on the objective psychometrics-CRT, BRT, RVIP, STM-compared with placebo. Pregabalin produced a limited, significant decrement on CFF and CTT and a significant effect on the LARS. Pregabalin was associated with improvement relative to placebo in BRT. The positive control, alprazolam, produced significant impairment on all objective measures and significant impairment on the LARS, thus establishing the sensitivity of the test battery used in the study. CONCLUSIONS: Pregabalin did not differ on most assessments from placebo, producing only minor, transient impairment on some objective cognitive and psychomotor measures, suggesting a relatively benign CNS side-effect profile.

Alprazolam↗
PubMed1998

Randomized, double-blind, cross-over trial comparing safety and efficacy of oral controlled-release oxycodone with controlled-release morphine in patients with cancer pain.

PURPOSE: Use of oxycodone for chronic cancer pain has been hampered by its short elimination half-life. This study was designed to compare the efficacy and safety of controlled-release formulations of oxycodone and morphine for cancer pain. PATIENTS AND METHODS: Thirty-two adult patients with cancer pain and a > or = 3-day history of stable analgesia with oral opioids provided written informed consent and were randomized to controlled-release oxycodone or controlled-release morphine for 7 days. To blind the study using available tablet strengths, the dose ratio of oxycodone to morphine was set at 1:1.5. On day 8, patients were crossed over to the alternate drug for 7 days. Pain intensity was assessed using a visual analog scale (VAS 0 to 100 mm) and a categorical scale (CAT 0 to 4). Side effects were assessed using a checklist (four-point categorical severity) and a nondirected questionnaire. Patients and investigators made blinded global ratings of efficacy and treatment preference. RESULTS: Twenty-three patients completed the study (10 men, 13 women). The VAS and CAT scores were (mean+/-SD) 23+/-21 and 1.2+/-0.8 on controlled-release oxycodone, and 24+/-20 (P=.43) and 1.3+/-0.7 (P=.36) on controlled-release morphine. No period or carryover effect was detected. There were no significant differences in adverse effects (P=.40) or ratings of efficacy and preference. The median oxycodone/morphine dose ratio was 1.5 and the maximum was 2.3. CONCLUSION: Controlled-release oxycodone is as safe and effective as controlled-release morphine in the treatment of cancer pain.

Administration, Oral↗
PubMed1991

The effect of phenylpropanolamine on 24-hour blood pressure in normotensive subjects administered indomethacin.

We evaluated the effect of phenylpropanolamine hydrochloride (PPA) in 14 young, healthy, normotensive women who concurrently received indomethacin. Subjects received sustained-release (SR) indomethacin 75 mg bid and were randomly assigned to receive double-blind SR PPA 75 mg/d or placebo for four days. After a six-day washout period, subjects were crossed over to the opposite four-day double-blind treatment. Following an additional six-day washout period, subjects received indomethacin placebo and PPA placebo during a final, single-blind four-day period. Twenty-four-hour blood pressure (BP) monitoring every 30 minutes and a 24-hour urine collection for prostaglandin E2 (PGE2) were performed on the fourth day of each treatment period. Compliance with the medication regimen was confirmed by drug concentrations, pill counts, and urinary PGE2 concentrations. Compared with the indomethacin and placebo treatment periods, the combination of indomethacin and PPA had no significant effect on mean systolic or diastolic BP during the 24-hour study period or during any four-hour interval. We conclude that the combination of SR PPA 75 mg/d and SR indomethacin 150 mg/d for four days has no adverse effect on BP in normotensive women.

Adult↗
PubMed1985

Abnormal neuronal excitability in hippocampal slices from kindled rats.

To determine if electrophysiological properties of hippocampal pathways are altered in kindled rats, extracellular recordings were made from hippocampal slices of rats kindled in the lateral entorhinal cortex and compared with those from implanted but unstimulated controls. Studies were made either 24 h or 28 days after the last kindled seizure and done in normal (3.5 mM) or elevated (7 mM) K+. The preparation of slices, data accumulation, and data analyses were done blind. One day or 28 days after the last kindled seizure, the proportion of slices with spontaneous epileptiform bursts recorded from the CA2/3 region in elevated K+ was significantly (P less than 0.001) increased in the kindled animals. The frequency of spontaneous burst firing was also increased and reached significance (P less than 0.02) at 28 days following the last kindling stimulus. One day after the last kindling stimulus, paired-pulse (GABAergic) inhibition in the CA1 region was decreased (P less than 0.001). Several measures suggested an increased synaptic inhibition in the dentate gyrus of slices from the kindled groups 1 day after kindling. Paired-pulse inhibition was increased (P less than 0.01), the current required to evoke a near-threshold population spike was increased (P less than 0.05), and the population spike amplitude was reduced for a given field excitatory postsynaptic potential (EPSP) (P less than 0.01). Twenty-eight days after the last kindling stimulus, however, paired-pulse inhibition in the dentate was slightly less in slices from kindled rats (P less than 0.005). In other respects the CA1 and dentate regions did not differ between kindled and control groups within 24 h of the last stage V seizure. Thus the maximum amplitudes of presynaptic fiber volley, population spike, and field-excitatory postsynaptic potential (EPSP) slope, and the number of population spikes evoked by a near-maximally effective afferent stimulus, were unchanged. In the CA1 region the input-output curve of field EPSP versus population spike, and the current intensity required to evoke a near-threshold population spike were also unchanged. In addition, no spontaneous bursts were recorded from CA1 in 3.5 mM K+. We conclude that either synapses or neurons intrinsic to the hippocampus are altered by kindling stimuli applied outside this brain area. The transient increase in inhibition in the dentate gyrus suggests that it may reflect a compensatory reaction to kindled seizures. In contrast, the long-lasting (at least 28 days) increase in burst firing in CA2/3 may represent a mechanism for the initiation or propagation of kindled seizures.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1996

Effects of oral creatine supplementation on multiple sprint cycle performance.

This study examined the influence of oral creatine monohydrate supplementation on repeated 10 s cycle ergometer sprint performance. Seventeen recreationally active males (mean +/- SD age, body mass, height, and peak oxygen uptake = 20.5 +/- 1.2 yr, 72.1 +/- 10.3 kg, 176.8 +/- 6.6 cm and 3.87 +/- 0.91 l.min-1, respectively) participated in the 16 day experiment. All subjects initially completed a VO2peak test and were then administered glucose (4 x 10 g per day) in a single blind fashion for four days, after which they completed the first series of multiple sprints (7 x 10 s). Following the sprints, subjects were matched on sprint performance and divided into two groups (n = 8, placebo (Pl); and n = 9, creatine (Cr)). For the following four days, diets were supplemented with either Cr (4 x 70 mg.kg-1 body mass per day mixed with 5 g glucose) or glucose (4 x 10 g per day); supplementation during this phase was double-blind. Subjects then repeated the multiple sprint and VO2peak tests. Measures of peak power output (PPO), mean power output (MPO), end-power output (EPO), and percent power decline were recorded during the sprints. Each 10 s sprint was separated by 30 s of passive recovery except for sprints five and six which were separated by five minutes. Venous blood was sampled at rest, immediately after sprint five, before sprint six, and following sprint seven for the analysis of plasma lactate and blood pH. Expired air was sampled for five minutes following sprint seven for the calculation of post-exercise VO2. Analysis of variance revealed that four days of Cr supplementation did not influence multiple sprint performance, plasma lactate, blood pH and excess post-sprint oxygen consumption. Furthermore, VO2peak was unchanged following Cr supplementation. The data suggest that either the four day period of Cr supplementation failed to significantly raise resting muscle [Cr], or that multiple sprint performance was not enhanced by increases in resting muscle [Cr].

Adult↗