The effect of 3 different exercise approaches on neck muscle endurance, kinesiophobia, exercise compliance, and patient satisfaction in chronic whiplash

Objective The purpose of this study was to compare the effects of 3 different exercise approaches on neck muscle endurance (NME), kinesiophobia, exercise compliance, and patient satisfaction in patients with chronic whiplash. Methods This prospective randomized clinical trial included 216 individuals with chronic whiplash. Participants were randomized to 1 of 3 exercise interventions: neck-specific exercise (NSE), NSE combined with a behavioral approach (NSEB), or prescribed physical activity (PPA). Measures of ventral and dorsal NME (endurance time in seconds), perceived pain after NME testing, kinesiophobia, exercise compliance, and patient satisfaction were recorded at baseline and at the 3- and 6-month follow-ups. Results Compared with individuals in the prescribed physical activity group, participants in the NSE and NSEB groups exhibited greater gains in dorsal NME (P =.003), greater reductions in pain after NME testing (P =.03), and more satisfaction with treatment (P .07). Conclusion Among patients with chronic whiplash, a neck-specific exercise intervention (with or without a behavioral approach) appears to improve NME. Participants were more satisfied with intervention including neck-specific exercises than with the prescription of general exercise

Nuclear singlet relaxation by scalar relaxation of the second kind in the slow-fluctuation regime

The singlet state of nuclear spin-1/2 pairs is protected against many common relaxation mechanisms. Singlet order, which is defined as the population difference between the nuclear singlet and triplet states, usually decays more slowly than the nuclear magnetization. Nevertheless, some decay mechanisms for nuclear singlet order persist. One such mechanism is called scalar relaxation of the second kind (SR2K) and involves the relaxation of additional nuclei ("third spins") which have scalar couplings to the spin-1/2 pair. This mechanism requires a difference between the couplings of at least one third spin with the two members of the spin-1/2 pair, and depends on the longitudinal relaxation time of the third spin. The SR2K mechanism of nuclear singlet relaxation has previously been examined in the case where the relaxation rate of the additional spins is on the time scale of the nuclear Larmor frequency. In this paper, we consider a different regime, in which the longitudinal relaxation of the third spins is on a similar time scale to the J-coupling between the members of the spin pair. This regime is often encountered when the spin-1/2 pair has scalar couplings to nearby deuterium nuclei. We show that the SR2K mechanism may be suppressed in this regime by applying a radiofrequency field which is resonant either with the members of the spin pair, or with the third spins. These phenomena are analyzed theoretically and by numerical simulations, and demonstrated experimentally on a diester of [13C2,2H2]-labeled fumarate in solution. </p