The aim of this study was to specify the effects of caffeine on maximal anaerobic power (Wmax). A group of 14 subjects ingested caffeine (250 mg) or placebo in random double-blind order. The Wmax was determined using a force-velocity exercise test. In addition, we measured blood lactate concentration for each load at the end of pedalling and after 5 min of recovery. We observed that caffeine increased Wmax [964 (SEM 65.77) W with caffeine vs 903.7 (SEM 52.62) W with placebo; P less than 0.02] and blood lactate concentration both at the end of pedalling [8.36 (SEM 0.95) mmol.l-1 with caffeine vs 7.17 (SEM 0.53) mmol.l-1 with placebo; P less than 0.01] and after 5 min of recovery [10.23 (SEM 0.97) mmol.l-1 with caffeine vs 8.35 (SEM 0.66) mmol.l-1 with placebo; P less than 0.04]. The quotient lactate concentration/power (mmol.l-1.W-1) also increased with caffeine at the end of pedalling [7.6.10(-3) (SEM 3.82.10(-5)) vs 6.85.10(-3) (SEM 3.01.10(-5)); P less than 0.01] and after 5 min of recovery [9.82.10(-3) (SEM 4.28.10(-5)) vs 8.84.10(-3) (SEM 3.58.10(-5)); P less than 0.02]. We concluded that caffeine increased both Wmax and blood lactate concentration.

This paper provides a summary review of the major biological features concerning the essential oil of turpentine, its origin and use in traditional and modern medicine. More precisely, the safety of this volatile fraction to human health, and the medical, biological and environmental effects of the two major compounds of this fraction (α-and β-pinenes) have been discussed. Key words:Spirits of turpentine, α-pinene, β-pinene Received: July 1, 2009. Accepted : September 28, 2009. Address reprint request to B. Mercier, UPRES EA 4183 "Lipides & Signalisation Cellulaire", Faculté des Sciences de la Vie, Université de Bourgogne 6, Boulevard Gabriel, F-21000 Dijon (e-mail: beamercier@laposte.net). ORIGIN OF TURPENTINEThe term "essential oil of turpentine" designates the terpenic oil, obtained by hydrodistillation of the gem pine. It is also named the "spirits of turpentine", "pine tree terpenic", "pine oleoresin", "gum turpentine", "terpenes oil" or "turpentine from Bordeaux". Due to its pleasant fragrance, the terpenic oil is used in the pharmaceutical industry, perfume industry, food additives and other chemical industries (household cleaning products, paintings, varnishes, rubber, insecticides, etc.) [1]. TRADITIONAL MEDICINE AND TURPENTINEThe eminent doctors of antiquity, Hippocrates, Dioscoride or Galien, used the terpenic oil for its properties against lung diseases and biliary lithiasis. In France, Thillenius, Pitcairn, Récamier and Martinet recommended it against the blennorrhoea and cystitis. Chaumeton, Peschiez, Kennedi, Mérat prescribed it against the neuralgias. It was also used in the treatment of rheumatism, sciatica, nephritis, drop, constipation and mercury salivation. Those scientists also recognized that the terpenic oil may be a booster at an average dose and may have a paralyzing activity at high doses. In Germany, (Rowachol and Rowatinex), Slovenia (Uroterp) and Poland (Terpichol and Terpinex), the traditional drugs for renal and hepatic diseases (especially against cholesterol stones in the gall bladder and the bile duct) contain α-and β-pinenes [2]. Modern phytotherapy describes the following properties of the terpenic oil: antiparasitic, analgesic, revulsive, disinfectant (external use); balsamic, active on bronchial secretion and pulmonary and genito-urinary tract infections, haemostatic, dissolving gallstones, diuretic, antispasmodic, antirheumatic, deworming, being an antidote for poisonings caused by phosphorus [3] and improving the ciliary and secretory activity in patients who present chronic obstructive bronchitis (internal use ) [4]. ENVIRONMENTAL IMPACT OF THE VOLATILE TURPENTINE FRACTIONThe most volatile components of turpentine are two terpenes: alpha (α) and beta (β) pinenes. They are the dominant odorous compounds emitted by trees, shrubs, flowers and grasses [25]. In the lower troposphere, and depending on the weather conditions at the top of the trees, these compounds can react with OH° radicals, ozone, NO 3 radical and O 2 . Indeed, the electric field in the canopy at...

We investigated the aerobic and anaerobic contributions to performance during the Wingate test in sprint and middle-distance runners and whether they were related to the peak aerobic and anaerobic performances determined by two commonly used tests: the force-velocity test and an incremental aerobic exercise test. A group of 14 male competitive runners participated: 7 sprinters, aged 20.7 (SEM 1.3) years, competing in 50, 100 and 200-m events and 7 middle-distance runners, aged 20.0 (SEM 1.0) years, competing in 800, 1,000 and 1,500 m-events. The oxygen uptake (VO2) was recorded breath-by-breath during the test (30 s) and during the first 20 s of recovery. Blood samples for venous plasma lactate concentrations were drawn at rest before the start of the test and during the 20-min recovery period. During the Wingate test mean power (W) was determined and three values of mechanical efficiency, one individual and two arbitrary, 16% and 25%, were used to calculate the contributions of work by aerobic (Waer,ind,16%,25%) and anaerobic (Wan,ind,16%,25%) processes. Peak anaerobic power (Wan,peak) was estimated by the force-velocity test and maximal aerobic energy expenditure (Waer,peak) was determined during an incremental aerobic exercise test. During the Wingate test, the middle-distance runners had a significantly greater VO2 than the sprinters (P < 0.001), who had significantly greater venous plasma lactate concentrations (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

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We investigated in rats the effect of 4 wk of hypodynamia on the respiration of mitochondria isolated from four distinct muscles [soleus, extensor digitorum longus, tibial anterior, and gastrocnemius (Gas)] and from subsarcolemmal (SS) and intermyofibrillar (IMF) regions of mixed hindlimb muscles that mainly contained the four cited muscles. With pyruvate plus malate as respiratory substrate, 4 wk of hindlimb suspension produced an 18% decrease in state 3 respiration for IMF mitochondria compared with those in the control group (P < 0.05). The SS mitochondria state 3 were not significantly changed. Concerning the four single muscles, the mitochondrial respiration was significantly decreased in the Gas muscle, which showed a 59% decrease in state 3 with pyruvate + malate (P < 0.05). The other muscles presented no significant decrease in respiratory rate in comparison with the control group. With succinate + rotenone, there was no significant difference in the respiratory rate compared with the respective control group, whatever the mitochondrial origin (SS, or IMF, or from single muscle). We conclude that 4 wk of hindlimb suspension alters the respiration of IMF mitochondria in hindlimb skeletal muscles and seems to act negatively on complex I of the electron-transport chain or prior sites. The muscle mitochondria most affected are those isolated from the Gas muscle.