Defining intensity domains from the end power of a 3-min all-out cycling test.

PURPOSE: The purpose of this study was to develop a modified version of a 3-min all-out cycling test (3MT) using equipment readily available to cyclists and to identify exercise intensity domains using the average power output over the last 30 s of the 3MT (end-test power (EP)). METHODS: Sixteen competitive cyclists (V(O2peak) = 60.3 +/- 8.3 mL.kg.min) completed three laboratory visits using their own bicycles and a power-measuring rear wheel. In visit 1, subjects performed an incremental load test to volitional termination on an electronically braked trainer (100 + 25 W every 4 min). Power output at lactate threshold was determined by absolute 4 mmol.L (OBLA-PO) and 1 mmol.L over exercise baseline (LT-PO). Power output at ventilatory threshold (VT-PO) was computed on the basis of the V-slope method. Power output at V(O2peak) (V(O2peak)-PO) was the mean power observed during the stage at which peak O2 consumption was recorded. In visits 2 and 3, subjects performed the 3MT using a progressive resistance trainer with Visit 2 as a familiarization trial. During Visit 3, EP was recorded. RESULTS: EP (273 +/- 52 W) was significantly greater than VT-PO, OBLA-PO, and LT-PO (232 +/- 64, 235 +/- 54, and 208 +/- 45 W, respectively) but significantly less than V(O2peak)-PO (288 +/- 56 W). EP was correlated with V(O2peak)-PO (r = 0.97), VT-PO (r = 0.87), OBLA-PO (r = 0.85), and LT-PO (r = 0.79) with regression estimates through the origin made using 105%, 86%, 86%, and 76% of EP, respectively. Demarcations for moderate- to heavy-intensity (LT-PO at 76% EP) and heavy- to severe-intensity (100% EP) domains may be estimated. CONCLUSION: The 3MT can be used to define exercise intensity in competitive cyclists using readily available equipment.

Universal method for the fabrication of detachable ultrathin films of several transition metal oxides.

Ultrathin films are important nanoscale structures that are used extensively in a variety of technological contexts. However, it has traditionally been difficult and costly to fabricate detachable and purely inorganic high aspect ratio films with controlled thickness and good uniformity. Here we report a versatile method to make separable purely inorganic membranes of various metal oxides such as Nb(2)O(5), TiO(2), WO(3), and Ta(2)O(5) with thicknesses ranging from 30 to 150 nm. Fluoride ions are migrated through the oxide film and upon arrival at the oxide-metal interface form a sacrificial soluble oxyfluoride layer. Fluorine also plays a role in controlling the porosity of the films. The study exposes the mechanism behind the detachment process that is largely due to the fast migration of fluoride anions relative to oxygen anions. The resulting films have a wide range of potential applications as catalysts or catalyst supports, filtration membranes, sensors, and more.