Because of geographical conditions in Japan, most of our rice is grown in paddies. It is very hard to work in paddies wearing a prosthesis.
The type of prosthesis, called the “DOLINGEL” or “Iron Leg”, are not suitable in paddies. The followings were our research and development objections;
1. To select strong light materials and design for the new prosthesis.
2. To have a simple design which could be cleaned easily after use.
3. To consider the problem of skin irritation on the stump end.
4. To select the best foot shape for easy lifting from the mud. From the above objectives, we improved it after actual use.
A summary of our improvement;
Aluminium was used as the main material for its light weight. The lower leg was made of plastic for its ease of clearing.
Regarding the knee joint settlement during work;
The old prosthesis was too unsteady to permit the worker to carry things. So we reconstructed it. By bending it forward, putting a long boot on the prosthesis was very easier. We used a system where by the whole lower leg section can be changed by a “one touch” prosedure. We put rubber on the sole to prevent slipping. We put a belt on the affected side. Its design is the result of our experiments and of actual field use.

High-intensity interval exercise (IE) leads to greater improvements in the arterial function than continuous exercise at moderate intensity (CE). However, few studies have been performed on the effects of the repetition exercise (RE) on the vascular endothelial function. The purpose of this study was to compare the effects of CE vs. IE vs. RE during aerobic exercise on the vascular endothelial function determined by flow-mediated vasodilation (FMD). Ten healthy male subjects randomly performed 3 trials as follows: CE (20-min cycling at 50%W_max), IE (10 × 1-min intervals cycling at 75%W_max interspersed with 1-min intervals cycling at 25%W_max), and RE (30 × 20-sec intervals cycling at 100%W_max interspersed with 20-sec intervals at rest). FMD was assessed at rest and 30 and 60 min after each exercise, and then the normalized FMD (nFMD) was calculated from the peak shear rate. The nFMD (a.u.) significant increased 30 min after IE (1.2 ± 0.2 to 3.0 ± 1.0, p<0.05) and increased 30 min after CE (1.0 ± 0.2 to 1.4 ± 0.2, n.s.) and returned to baseline at 60 min after both exercises, while the nFMD decreased 30 min after RE (1.3 ± 0.2 to 1.2 ± 0.1, n.s.) and was sustained at 60 min. The nFMD value at 30 min after IE was significantly greater than that at 30 min after RE (3.0 ± 1.0 versus 1.2 ± 0.1, p<0.05). These results suggest that RE may lead to a less improvement in the vascular endothelial function than CE and IE.

Endurance exercises such as cycling and running are useful for improving the arterial function and preventing cardiovascular disease (CVD). However, subjects suffering from spinal cord injury (SCI) or lower limb osteoarthritis (OA) cannot perform these kinds of lower limb exercises. Recently, electrical muscle stimulation (EMS) has been shown to be able to increase the muscle strength and blood flow and improve the peripheral circulation. Arm-cranking exercises with EMS may therefore be able to reduce the risk of CVD for patients with SCI and lower OA. However, this point has not been fully clarified. The purpose of this study was to assess the effect of submaximal arm-cranking exercise with EMS on arterial stiffness. Ten healthy young subjects performed submaximal arm-cranking exercise alone (A) and submaximal arm-cranking exercise with EMS (A+E). In the A+E trial, the submaximal arm-cranking exercise was performed at 30%VO2 max for 20 min while EMS was applied to their thigh and calf muscles during the exercise. The brachial-ankle pulse wave velocity (ba-PWV), systolic and diastolic blood pressure (SBP/DBP) and heart rate (HR) were measured before and after each exercise. Immediately after the exercise session, the HR of the subjects in the A+E trial was significantly elevated in comparison to those in the A trial. The SBP and DBP did not differ between the two trials to a statistically significant extent. In the A+E trial, the ba-PWV was significantly reduced immediately after exercise in comparison to the A trial (1082.6 ± 105.9 cm·sec-1 vs. 1191.7 ± 86.7 cm·sec-1, p < 0.05). These findings suggest that arm-cranking exercise with EMS reduces arterial stiffness and might be useful for reducing the risk of CVD.

High-intensity interval exercise leads to greater improvements in the vascular endothelial function than continuous exercise at moderate intensity. However, few studies have been performed on the effects of repetition exercise consisting of high-intensity exercise followed by complete rest on the arterial function. Therefore, the purpose of this study was to investigate the effects of repetition exercise on the vascular endothelial function determined by flow-mediated vasodilation (FMD). Eleven healthy male subjects completed two exercise sessions on a cycle ergometer in a counterbalanced order. The exercise sessions were 20 min cycling at 50% maximal work rate (Wmax) (continuous exercise, CE) and 20 × 20-sec intervals at 100%Wmax interspersed with 40-sec intervals at complete rest (repetition exercise, RE). Before and after each protocol, the brachial systolic and diastolic blood pressure were measured in the supine position. Relative FMD was assessed at rest and 30 and 60 min after each exercise regimen, and then the normalized FMD (nFMD) was calculated from the peak shear rate. The FMD significantly increased 30 min after RE (8.2 ± 1.5% to 11.5 ± 3.1%, p<0.01) and non-significantly increased 30 min after CE (7.5 ± 1.6% to 8.1 ± 2.1%, n.s.) before returning to baseline at 60 min after both exercise regimens. The FMD value at 30 min after RE was significantly greater than that at 30 min after CE (p<0.01). The nFMD (a.u.) significantly increased 30 min after RE (1.38 ± 0.64 to 2.00 ± 0.94, p<0.05) and non-significantly increased 30 min after CE (1.20 ± 0.54 to 1.49 ± 0.57, n.s.) before returning to baseline at 60 min after both exercise regimens. These results suggest that repetition exercise may lead to an acute improvement in the vascular endothelial function.