Creatine Monohydrate and Conjugated Linoleic Acid Improve Strength and Body Composition Following Resistance Exercise in Older Adults

Aging is associated with lower muscle mass and an increase in body fat. We examined whether creatine monohydrate (CrM) and conjugated linoleic acid (CLA) could enhance strength gains and improve body composition (i.e., increase fat-free mass (FFM); decrease body fat) following resistance exercise training in older adults (>65 y). Men (N = 19) and women (N = 20) completed six months of resistance exercise training with CrM (5g/d)+CLA (6g/d) or placebo with randomized, double blind, allocation. Outcomes included: strength and muscular endurance, functional tasks, body composition (DEXA scan), blood tests (lipids, liver function, CK, glucose, systemic inflammation markers (IL-6, C-reactive protein)), urinary markers of compliance (creatine/creatinine), oxidative stress (8-OH-2dG, 8-isoP) and bone resorption (Ν-telopeptides). Exercise training improved all measurements of functional capacity (P<0.05) and strength (P<0.001), with greater improvement for the CrM+CLA group in most measurements of muscular endurance, isokinetic knee extension strength, FFM, and lower fat mass (P<0.05). Plasma creatinine (P<0.05), but not creatinine clearance, increased for CrM+CLA, with no changes in serum CK activity or liver function tests. Together, this data confirms that supervised resistance exercise training is safe and effective for increasing strength in older adults and that a combination of CrM and CLA can enhance some of the beneficial effects of training over a six-month period. Trial Registration. ClinicalTrials.gov NCT0047390

Dabigatran attenuates thrombin generation to a lesser extent than warfarin: could this explain their differential effects on intracranial hemorrhage and myocardial infarction?

Compared with warfarin, dabigatran is associated with less intracranial hemorrhage, but an increased risk of myocardial infarction. To explore these phenomena, we compared their effects on thrombin generation. Thrombin generation in plasma from 10 patients taking therapeutic doses of warfarin (mean INR 2.6) was compared with that in plasma containing 250 ng/mL dabigatran. Although lag times were similar when thrombin generation was induced by recalcification or with a range of tissue factor concentrations, there was a greater reduction in peak thrombin generation and endogenous thrombin potential in plasma from warfarin-treated patients than in dabigatran-containing plasma. Similar results were obtained when thrombin generation was determined in plasma samples from 18 warfarin or 36 dabigatran treated patients entered into the RE-LY trial. Warfarin suppresses thrombin generation more efficiently than dabigatran. Greater suppression of normal hemostatic mechanisms in the brain and pathological thrombosis at sites of atherosclerotic plaque disruption may explain the higher rate of intracranial bleeding and lower rate of myocardial infarction with warfarin compared with dabigatra