This study aimed to examine characteristics of physical functions, physical activity, and cognitive functions among community-dwelling older people who stopped driving automobiles. Participants were 589 community-dwelling older people (age: 65–89, 71.4 ± 5.1 years; 403 men, 186 women). The participants underwent nine physical assessments—hand grip strength, knee extension strength, timed up-and-go test, chair stand, one leg standing with open eyes, functional reach, vertical jump, preferred gait speed, maximal gait speed—and were evaluated for physical activity; and five cognitive assessments—the Mini-Mental State Examination (MMSE), Logical Memory I and II (WMS-R LM-I, LM-II) subtests of the Wechsler Memory Scale-Revised; and Trail Making Test A and B (TMT-A, TMT-B). They were divided into current driver (379 men, 169 women) and driving cessation (24 men, 17 women) groups. Among men, the driving cessation group had poorer vertical jump, TMT-A, and TMT-B results, while women had poorer hand grip strength, one leg standing with open eyes, WMS-R LM-II, and LM-II results, and longer inactivity time, compared with the current driver group and adjusted for covariates (P < 0.05 for all). The findings suggest driving cessation among community-dwelling older people is significantly associated with poorer physical functions, physical activity, and cognitive functions compared with those in current drivers.

This study examined whether physical and cognitive function was independently associated with risk of Musculoskeletal Ambulation Disorder Symptom Complex (MADS) in community-dwelling older people. We examined 640 older people (315 men, 325 women; 65–89 years). We assessed physical performance by one-leg standing with eyes open, timed up and go (TUG), muscle strength, muscle power, and gait speed. Cognition was assessed using Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR), and Trail-Making Tests (TMT) A and B. We divided participants by physical function into “MADS” (one-leg standing < 15s or TUG ≥ 11s) and “non-MADS”, and identified cognitive impairment if MMSE was < 27 and CDR ≥ 0.5. We also grouped by sex and age (younger-old: 65–74 years and older-old: 75–89 years), and controlled for age, Body Mass Index, education and steps. Physical and cognitive function was significantly worse in the MADS groups. The younger-old men had poorer muscle strength, muscle power and TMT-A. The younger-old women had poorer muscle power, gait speed, MMSE and TMT-B. Older-old men had poorer muscle strength, and older-old women poorer gait speed (P < 0.05). The MADS groups also had significantly higher adjusted odds ratio (OR) for cognitive impairment (younger-old men: OR: 4.62; 95% confidence interval [CI]: 1.08–19.8; younger-old women: OR: 6.09; 95% CI: 1.03–35.9; P < 0.05). This study suggested that poorer physical and cognitive function was significantly associated with the risk of MADS, and these associations may be differ with sex and age.

Recent studies indicate that exercise with a low muscle glycogen state enhances exercise-induced metabolic adaptation. However, it is unclear whether metabolic adaptation is involved with muscle glycogen depletion level. In this study, we investigated the effects of prior muscle glycogen depletion level on metabolic response during acute continuous exercise. Seven men completed two experimental trials consisting of two exercise sessions per day. During the first session, participants performed either intermittent exercise (IE) at VO₂max (the IE-CE trial) or continuous exercise (CE) at lactate threshold (the CE-CE trial). During the second session, participants performed 60 minutes of CE at lactate threshold. During this second session, fatty acid oxidation (FAO) was calculated. To determine muscle glycogen content and PGC-1α and PDK-4 mRNA abundance, muscle biopsies were taken at rest after the first session and 2 hours after the second session. After the first session, muscle glycogen content was significantly lower in the IE-CE trial (38.1±5.0 mmol/kg w.w.) than in the CE-CE trial (56.7±10.2 mmol/kg w.w.), P<0.05. FAO was higher in the IE-CE trial than the CE-CE trial at baseline and 15 minutes after the second session (both P<0.05). PGC-1α mRNA abundance increased after exercise (IE-CE, 5.9±2.5; CE-CE, 2.6±1.3-fold; P<0.1). PDK-4 mRNA abundance increased significantly after exercise (IE-CE, 22.2±8.8; CE-CE, 31.5±10.6-fold; P<0.05). PGC-1α and PDK-4 mRNA were not significantly different between the trials. In conclusion, continuous exercise with a slightly muscle glycogen-depleted state induced similar level of PGC-1α and PDK-4 mRNA expression, but attenuated FAO, compared to exercise with a moderate muscle glycogen-depleted state.

Recent health guidelines suggest that children should accumulate 60 minutes of physical activity (PA) of moderate to vigorous intensity every day. The purpose of this study was to assess PA on weekdays, in addition to physical fitness, in elementary school children during short-term extracurricular activities (EA). Children from an elementary school (n=160) who carried out EA were assigned to the EA group, and children from the neighboring elementary school (n=210) comprised the non-EA group. A physical fitness test was applied to evaluate physical fitness in pupils. Moreover, 48 children (EA, n=24; non-EA, n=24) wore a pedometer with a uniaxial accelerometer to determine the amount of PA and time spent in moderate- to vigorous-intensity PA. The PA of EA was evaluated with the exception of the short program (10 min). Jogging distance of the EA was 1357 ± 333 m, average speed was 170 ± 42 m/min. The estimated energy consumption of jogging was 55 ± 19 kcal. Multiple items of the physical fitness test scored significantly higher in the EA group than in non-EA subjects. Total step counts were 15485 ± 1915 steps/day for the EA group and 12363 ± 2464 steps/day for the non-EA group on weekdays (p<0.001). Time spent in moderate- to vigorous-intensity PA on weekdays was 61.6 ± 10.0 min/day for EA children and 46.5 ± 12.9 min/day for non-EA children (p<0.001). In addition, the extent of PA in the EA group was higher than the amount recommended for children in general. This study suggested that short-term EA are related to both the fitness and PA levels of elementary school children.

It is well known that decreased physical performance induces the decreased activity of daily living and increment of mortality rate in elderly subjects. On the other hand, a prolonged heart rate corrected-QT (QTc) interval is associated with an increased risk of cardiac sudden death and cardiac autonomic dysfunction. We investigated the associations between physical performance and QTc interval in elderly subjects. The subjects included 605 elderly persons (274 men and 331 women, age; 71.2±4.7 years) without a history of cardiovascular disease and taking cardioactive drugs. Resting 12-leads electrocardiography was measured after more than 5 minutes of rest. The QTc interval was calculated according to Bazett’s formula. The physical fitness test was performed to determine the physical performance (muscle strength, balance and walking abilities). The subjects were divided into four categories, which were defined as equally quantile distributions of QTc interval. The physical performance levels were significantly lower in the longest QTc interval group compared to the shortest QTc interval group in both men and women (p<0.05, respectively). Moreover, after adjusting for the age, the physical performance levels were significantly lower in the longest QTc interval group compared to the shortest QTc interval group, especially, this relationship was observed in late-stage elderly group (p<0.05, respectively). These results suggest that decreased physical performance levels were also associated with prolonged QTc interval in elderly subjects.

This study investigated the effects of exercise intervention with a 12-week slightly-weighted shoe on lower-limb skeletal muscle and gait patterns in the elderly. A total of 29 healthy elderly Japanese who had irregular walking habits were randomly assigned to either slightly-weighted-shoe (WS group, n = 14; Age, 70.6 ± 5.7 years; WS, 493 g) or normal-shoe (NS group, n = 15; Age, 69.3 ± 6.9 years; NS, 293 g) intervention groups. The participants were instructed to maintain their normal daily physical activity (PA) during the intervention period. Segmental intracellular water (ICW) and muscle thickness (MT) were measured as an index of skeletal muscle mass in the lower limb, and kinematic gait data were acquired by motion analysis. Walking stability was assessed as a standard deviation of the vertical fluctuation in whole-body center of mass (COM fluctuation). The daily PA was monitored using an accelerometer and an activity record. ICW in the upper leg and MT of rectus femoris increased significantly in the WS group compared with the NS group (ICW: 13.8% vs. 2.2%, MT: 12.1% vs. 1.3%), while COM fluctuation was significantly reduced in the WS group (p<0.05) during normal walking. The present study demonstrated that interventions with a slightly-weighted-shoe may be able to increase muscle volume in the upper leg and change gait patterns in the healthy elderly.

This study sought to determine whether aerobic exercise training affects cognitive functioning among semi-independent (> 75 years) and independent elderly people. Seventy-six semi-independent and independent elderly subjects were divided into the following groups: semi-independent control (n = 16); semi-independent training (n = 13); independent control (n = 22); independent training (n = 25). During the 12-week intervention, subjects in both training groups performed a bench-stepping exercise at the intensity of the lactate threshold. Subjects were assessed at baseline and post-intervention using the Frontal Assessment Battery test (FAB), the Modified Mini-Mental State Exam (3MS), and a bench-stepping test of aerobic capacity. During the intervention, FAB scores improved only in the semi-independent training group (p = .002), while 3MS and MMSE scores improved in both the semi-independent training (p = .032 and p = .004) and independent training groups (p = .001 and p = .013). FAB and 3MS scores were higher in the semi-independent training (p = .001 and p = .002) compared with the semi-independent control group after the intervention. Finally, post-intervention scores for FAB, and 3MS in the semi-independent training group almost reached the baseline levels of the independent control and independent training groups. These results indicate that moderate intensity bench-stepping exercise training can improve cognitive and frontal lobe functioning in semi-independent elderly people, almost to the level exhibited by independent elderly people.

The decrease of muscle glycogen may be useful for the improvement of endurance performance. Intense anaerobic exercise requires a high rate of glycogen utilization, but consecutive intense anaerobic exercises induce a pronounced decline of external power and muscle glycogen consumption. We hypothesized that a long rest period between consecutive intense anaerobic exercises may aid in sustaining external power and glycogen consumption. Secondly, we hypothesized that active rest (AR) during the long resting period may be more effective than passive rest (PR).Six subjects performed four 30-second Wingate tests (WAnT) with a 4-minute recovery between each bout (Consecutive method). The subjects also performed a similar exercise procedure, but with a 30-minute seated resting period after the second bout (PR method).The other six male subjects performed four 30-second WAnTs with a 4-minute recovery between each bout, with 30-minutes of cycling at 40% VO₂max after the second bout (AR method). The subjects also performed PR method.The total work during the third and fourth bouts was greatest under the AR condition, followed by the PR condition, and finally the Consecutive method (p<0.05 for all comparisons). Blood lactate concentration during resting period was significantly lower, while muscle glycogen consumption was greater AR method than PR method (p<0.05 for both).A long resting period between consecutive intense anaerobic exercises may prevent the decline in external power and work. Additionally, AR has more favorable effects on muscle glycogen consumption, resulting in very low muscle glycogen levels, even with a small total amount of exercise.

Angiotensin I converting enzyme (ACE) gene Insertion/Deletion (I/D) polymorphism was first shown as a genetic factor which influences human physical performance in 1998. Since then, various gene polymorphisms which influence physical performance and trainability have been reported. ACE is a key enzyme which produces angiotensin II in the renin-angiotensin system, and its activity was determined by I/D polymorphism. Many studies indicate that the I/I genotype is frequently found in elite endurance athletes, while the D/D genotype is frequently found in power-oriented elite athletes. Longitudinal studies show that the D/D genotype may contribute to enhanced strength trainability. However, it is still unclear whether the I/I genotype enhances endurance trainability. Therefore, the ACE gene I/D polymorphism can be a genetic factor which influences human physical performance.

Double product (DP, heart rate × systolic blood pressure) during an incremental exercise test has been known to start to increase steeply at a workload, i. e. double product break point (DPBP), which corresponds to the blood lactate threshold. The study was to investigate the relationship between DP transition and ST segment depression in electrocardiogram during exercise. Thirty-one patients of angina pectoris of effort and 140 elderly persons performed a continuous incremental exercise test using a stationary bicycle ergometer. During the entire test, HR and blood pressure were measured every 15 seconds and an electrocardiogram was recorded continuously. DPBP was then calculated. In ten of the 31 patients, ST level depression above -0.1 mV with a typical ischemic form in lead V 5 was observed during the test. However, workload at the DPBP was significantly lower than that of the ischemic threshold on the electrocardiogram (i. e. -0.1mV of ST depression) in relation to work load (46+/-16 vs. 78+/-20 watts), HR (96+/-13 vs. 117+/-13 bpm), SBP (160+ /-20 vs. 199+/-31 mmHg) and DP (15400+/-3400 vs. 23400+/-4900 bpm × mmHg) . In elderly persons, DPBP could be determined without the ischemic ST depression in 96% of 327 tests. This study indicated that the DPBP would be an objective index of exercise intensity with lower risk for exercise prescription in cardiac patients and elderly persons.