Previous studies of contracting muscle with low loading and partial vascular occlusion demonstrated hypertrophy and strength adaptations similar to and exceeding those observed with traditional moderate to high resistance (Shinohara M, Kouzaki M, Yoshihisa T, and Fukunaga T. Eur J Physiol 77: 189-191, 1998; Takarada Y, Takazawa H, Sato Y, Takebayashi S, Tanaka Y, and Ishii N. J Appl Physiol 88: 2097-2106, 2000; Takarada Y, Sato Y, and Ishii N. Eur J Physiol 86: 308-314, 2002). The purpose of the study was to determine the anabolic and catabolic hormone responses to light resistance exercise combined with partial vascular occlusion. Three experimental conditions of light resistance with partial occlusion (LRO), moderate resistance with no occlusion (MR), and partial occlusion without exercise (OO) were performed by eight healthy subjects [mean 21 yr (SD 1.8)]. Three sets of single-arm biceps curls and single-leg calf presses were completed to failure with 1-min interset rest periods. Workloads of 30 and 70% one repetition maximum for each exercise were lifted for the LRO and MR trials, respectively. Blood samples were taken preexercise, postexercise, and 15 min postexercise for each experimental condition. Lactate increased significantly in the LRO and MR trials and was not significantly different from each other at any time point. Growth hormone (GH) increased significantly by fourfold from pre- to postexercise in the LRO session but did not change significantly during this time period in the MR and OO trials (8.3 +/- 2.3 vs. 2.1 +/- 1.2 and 2.6 +/- 0.94 microg/l; respectively, P < 0.05). There were no changes in resting total testosterone [T; mean 15.7 +/- 1.6 (SE) nmol/l], free testosterone (FT; 54.1 +/- 4.5 pmol/l), or cortisol (267.6 +/- 22 nmol/l) across all trials and times. In conclusion, with similar lactate responses, light exercise combined with partial vascular occlusion elicits a greater GH response than moderate exercise without occlusion but does not affect T, FT, or cortisol.

Seven weight-trained males performed both light resistance with partial occlusion (LRO: 30% 1 RM) and moderate resistance (MR: 70% 1 RM) to failure to ascertain whether blood protein carbonyls (PC) and glutathione status was altered compared to partial occlusion (PO) in a counterbalanced fashion. PO was identical in duration to the LRO session and all sessions were on separate days. PC did not differ for the three conditions at PRE (0.05 nM mg protein(-1)). PC significantly increased for PO and MR over time and was greater than the LRO treatment at POST (0.13 nM mg protein(-1)). The GSSG/TGSH ratio at PRE did not differ across treatments (8%) whereas the ratio at POST was significantly elevated for PO and MR treatments (17%). In contrast, no change occurred for the LRO session at any time. These results indicate that MR to failure and PO can significantly increase blood oxidative stress but LRO did not elicit oxidative stress.

The purpose of the study was to determine how manipulation of peripheral blood flow during resistance exercise using a light load affected perception and physiological measures compared with moderate load resistance exercise and a control trial. Seven subjects performed a 3 (session) by 2 (biceps curls and calf extensions) within-subjects study that was randomized and counterbalanced across 3 weeks. The 3 sessions included (a) light resistance exercise (3 sets to failure) at 30% of 1 repetition maximum (1RM) with partial occlusion (LRO), (b) moderate resistance at 70% of 1RM with no occlusion (MR), and (c) partial occlusion without exercise (OO). Ratings of perceived exertion (RPE), pain, and heart rate were assessed immediately after each set, whereas blood samples were taken before, immediately after, and 15 minutes after exercise. Results demonstrated that RPE and pain were lower in the OO condition than that in the MR and LRO conditions for biceps curls and calf extensions, Fs(2 ,24) = 22.75, 20.86, ps < 0.0001 and Fs(2,24) = 18.95, 24.52, ps < 0.01; however, no significant differences were noted between MR and LRO conditions. Heart rate was significantly higher for the LRO condition when compared with the MR trial, F(2,18) 20.12, p < 0.001. Results suggest that when partial vascular occlusion with a light load was applied, both pain and effort sense were altered to a similar degree as moderate loads but no occlusion. The practical application of results were that individuals may be better able to tolerate perceptual change at low loads with partial occlusion because joint stress may be minimized while local muscle metabolic demands increase, making resistance training maximally effective and minimally stressful on joints. Perceptual tracking of effort and pain may aid coaches who attempt this protocol.

Phosphor thermography, relying on the temperature dependence of the decay time of photoluminescence from suitable phosphors, provides remote measurement of the temperature of components. Such a phosphor is yttrium oxide doped with europium (Y2O3:Eu). Associated with this phosphor is also a rise time. Demonstrated is that the rise time is also temperature dependent, as a result of known electronic transitions within the Eu ions. For the phosphor Y2O3:Eu (3.4 at.%), the rise time is an activated process in the temperature region between 25 and 850 °C. Faster than the decay time, the rise time offers the opportunity for measurement of higher velocity components.

Polycrystalline films of ZnS with a slight excess of S have been grown on (100) Si by congruent sublimation from a single Knudsen cell. Intense blue emission is observed at 460 nm from room-temperature photoluminescence studies, and is ascribed to S-Zn vacancies acting as self-activated (SA) centres. The emission is quenched by the addition of Zn from a second Knudsen cell, which also causes the growth of a luminescent peak centred on 678 nm. No reduction in the SA luminescence is seen when co-sublimating ZnS and AgS. implying that it is not possible to remove the S-vacancy completely. Quenching of the blue emission occurs when Mn, instead of Zn, is added to the ZnS films, providing direct evidence of M n incorporation into Zn vacancies. At the optimum M n concentration, the intensity of t h e Mn emission at 580 nm is comparable to t h e blue emission (460 nm) from the undoped ZnS films.