Purpose We aimed to measure 1) the dynamics of locomotor fatigue during constant supra-critical power cycling and 2) the magnitude of any reserve in locomotor power at intolerance to constant and ramp-incremental cycling in recreationally active volunteers. Methods Fifteen participants (7 women and 8 men, 22 ± 3 yr, 3.34 ± 0.67 L·min−1 V˙O2peak) completed ramp-incremental and very-heavy constant power (205 ± 46 W) exercise to the limit of tolerance. Immediately after intolerance, the ergometer was switched into the isokinetic mode, and participants completed a short (~5 s) maximal isokinetic effort at 70 rpm. The time course of locomotor fatigue during constant supra-critical power exercise was characterized with these short maximal isokinetic sprints at 30, 60, 120, and 180 s and at the limit of tolerance. Each bout was terminated after the isokinetic sprint. Results Constant power exercise duration was 312 ± 37 s. Isokinetic power production values at 30, 60, 120, and 180 s and at the limit of tolerance (at 312 ± 37 s) was 609 ± 165, 503 ± 195, 443 ± 157, 449 ± 133, and 337 ± 94 W, respectively. Of the total decline in isokinetic power, ~36% occurred within the first minute of exercise, and significant (P < 0.05) reductions in isokinetic power occurred at all time points versus the baseline maximal isokinetic power (666 ± 158 W). In addition, a significant power reserve of 132 ± 74 W (64% of the task requirement) and 119 ± 80 W (47%) was present at the limit of constant power and ramp-incremental exercise, respectively. Conclusions Locomotor fatigue occurred rapidly during supracritical power exercise with pseudo-exponential kinetics. Instantaneous isokinetic power production at the limit of tolerance exceeded that of the task requirement, regardless of the constant or ramp work rate profile. Thus, the perceptual and physiologic limits were dissociated at the limit of tolerance in recreationally active volunteers.

The asymptote of the hyperbolic power-duration relationship, critical power (CP), demarcates sustainable from non-sustainable exercise. CP is a salient parameter within the theoretical framework determining exercise tolerance. However, measuring CP is time consuming – typically 4 constant-power exercise tests to intolerance, or a 3-min all-out sprint is required.To determine whether 30 s of maximal isokinetic cycling, immediately following the limit of tolerance, approximates CP.Fifteen participants (7 women, 8 men, 23±5 yr, 71±12 kg, V̇O2peak 4.39±1.04 L·min−1; 61±9 mL·kg·min−1) completed 4 constant supra-CP exercise tests to intolerance. Each test was followed immediately by a 30 s maximal isokinetic effort at 80 rpm. Mean isokinetic power was compared to the known CP.Mean±SD CP was 159±47 W (CI95 133, 185 W). Maximal isokinetic power immediately following intolerance was greater (p<0.05) than CP in all but one comparison (181±51 vs. 159±47 W; p>0.07). However, this closest estimation, following the longest duration constant-power test, resulted in 21 W of mean bias and wide limits of agreement (±84 W).Isokinetic power measured immediately following intolerance consistently overestimated critical power. Thus, an adjunct of 30 s maximal isokinetic cycling immediately following the limit of tolerance does not approximate critical power.

Financial market infrastructures (FMIs) have evolved as core elements of highly intermediated financial markets partly due to the technological limitations of the time when they were first designed. Organizations and firms were unable to share records without having to entrust a single party to manage them; hence this phenomenon of intermediation has led to significant information silos. Simultaneously, it has driven the structure of business models, as well as regulatory supervision and oversight, in ways that furthered intermediation and also created a misalignment of incentives and risk taking between entities now categorized as systemically important financial institutions (SIFIs) and systemically important financial market infrastructures. Over time, this consolidation has led to highly concentrated FMIs and with it, concentrated risks. Some of these risks go beyond the credit risks of just one or two institutions, becoming instead systemic risks that are continuously monitored by regulatory bodies. Over the past decade, advances in public key cryptography, hash functions, virtualization, distributed consensus, multiparty computation, and peer-to-peer networking have led to experimentation around record sharing between erstwhile competitive firms. Over the past five years, a series of independent efforts has chaperoned regulatory requirements into a digital, automated state that enables secure information sharing in full compliance with the law, while simultaneously enabling market participants to mutualize infrastructure that would otherwise be run by a single trusted party. With these developments, many of the services that centralized intermediaries currently provide could potentially be replaced by decentralized infrastructures or decentralized financial market infrastructure (dFMI). dFMI also enables a change in business structure, where a re-alignment of incentives can take place such that those firms taking risks can fully bear the consequences of these risks.

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