Leg strength and the VO2 max of older men.

The purpose of the study was to determine if leg strength limits VO2 max and the ability to reach a plateau during VO2 max test in older men during cycle ergometry. Men aged 70-80 years were randomly selected into a strength training (ST, n=12) 3 times weekly for 16 weeks, followed by 4 weeks detraining or a non-training control group (C, n=12). Leg strength and VO2 max were assessed every 4 weeks for 20 weeks; body composition and cardiac function were assessed before and after 16 weeks training and after 4 weeks detraining. Leg strength, upper leg muscle mass (ULMM), arterial-venous O2 difference (a-v O2 difference) and VO2 max increased in the ST group (95±0.6%, 7±0.7%. 6.2±0.5% and 8±0.8%, respectively; P<0.05) after 16 weeks training. After 4 weeks detraining, gains in ULMM (50%) and strength (75%) were retained, but VO2 max and a-v O2 difference returned to pre-training levels. There was no change in the ability of the participants to reach a plateau during VO2 max testing over the 20-week study. These findings indicate that leg strength may not limit either VO2 max or the ability to plateau during VO2 max tests in older men during cycle ergometry.

Erythrocyte aggregation and neutrophil function in an aging population.

There are limited investigations which have examined the relationship between neutrophil activation and erythrocyte aggregation in older persons. The purpose of the present study was to investigate the relationship between neutrophil activation and erythrocyte aggregation (EA) in an aging population. Twenty-eight male and female subjects were allocated into one of four groups with 7 participants in each group (group 1, 20-29 years; group 2, 30-39 years; group 3, 40-49 years; group 4, 50-59 years). EA was determined using the Myrenne aggregometer. Neutrophil function (respiratory burst and phagocytic activity) was assessed using flow cytometry. EA was found to increase with age. An ANOVA showed a significant (p < 0.05) increase for EA in autologous plasma in group 4 compared to groups 1 and 2. An ANOVA and Pearson's correlation showed that phagocytic activity decreased with age. Furthermore, a positive correlation between stimulated phagocytic activity and erythrocyte aggregability at low shear in 3% dextran-70 solution was observed. The current investigation suggests a decrease in neutrophil phagocytic activity with age and EA was increased with age. Additionally, the current study is novel as it suggests a possible relationship between neutrophil phagocytic activity and erythrocyte aggregability.

Thermoregulatory responses to exercise and warm water immersion in physically trained men with tetraplegia.

OBJECTIVE: To compare thermoregulatory responses of highly trained men who are tetraplegic during 40 min exercise at 65% [Vdot]O(2) peak and 60 min immersion in 39 degrees C water. METHODS: Four physically trained men who are tetraplegic participated in three laboratory visits. The first visit involved familiarisation and then determination of [Vdot]O(2) peak using open circuit spirometry during an incremental test to exhaustion with each man propelling his sport wheelchair on a motor driven treadmill. The order of second and third visits was randomly allocated. Visit 2 involved 40 min of exercise at 65% [Vdot]O(2) peak propelling each man's sport wheelchair on treadmill. Visit 3 involved sitting immersed to nipple line in 39 degrees C water for 60 min. Venous blood was obtained pre, during and after each intervention and analyzed for haemoglobin, haematocrit and changes in plasma volume were calculated. Separated plasma was analyzed for noradrenalin and adrenalin (high performance liquid chromatography). Heart rate, rectal temperature, and sweat rate estimated from a sweat capsule placed on forehead (dew point hygrometry) were recorded throughout. RESULTS: [Vdot]O(2) peak and HR max of these subjects were 1.14+/-0.16 l.min(-1) and 99+/-4 b.min(-1) respectively. Heart rate preimmersion was 67+/-4 b.min(-1) rising to 75+/-4 b.min(-1) after 40 min and 87+/-3 b.min(-1) after 60 min immersion. Heart rate was 68+/-3 b.min(-1) pre-exercise rising to 91+/-5 b.min(-1) after 40 min exercise. Rectal temperature rose from 35.97+/-0.30 degrees C pre immersion to 37.32+/-0.51 degrees C after 60 min immersion, and from 36.42+/-0.20 degrees C pre-exercise to 36.67+/-0.19 degrees C after 40 min exercise. Haemoconcentration occurred during 40 min of exercise and haemodilution occurred throughout 60 min of water immersion. Three participants demonstrated no sweating on the forehead during immersion or exercise. One subject commenced sweating after 20 min exercise and after 5 min of immersion. CONCLUSION: Compared to exercise, immersion was associated with a lower heart rate, a lower plasma noradrenalin concentration and an expanded plasma volume. When considering exercise or warm water immersion as therapeutic modalities in men who are tetraplegic, attention should be paid to heat gain and changes in plasma volume.

Effect of ramp slope on ventilation thresholds and VO2peak in male cyclists.

This study investigated the effect of 10 W*min(-1) (Slow ramp, SR), 30 W*min(-1) (Medium ramp, MR) and 50 W*min(-1) (Fast ramp, FR) exercise protocols on assessments of the first (VT1) and second (VT2) ventilation thresholds and peak oxygen uptake (VO(2)peak) in 12 highly-trained male cyclists (mean +/- SD age = 26 +/- 6 yr). Expired gas sampled from a mixing chamber was analyzed on-line and VT1 and VT2 were defined as two break-points in 20-s-average plots of pulmonary ventilation (V(E)), ventilatory equivalents for O(2) (V(E)/VO(2)) and CO(2) (V(E)/VCO(2)), and fractions of expired O(2) (F(E)O(2)) and CO(2) (F(E)CO(2)). Arterialized-venous blood samples were analyzed for blood-gas and acid-base status. VO(2)peak was significantly lower (p < 0.05) for SR (4.65 +/- 0.53 l small middle dot min(-1)) compared to MR (4.89 +/- 0.56 l *min(-1)) and FR (4.88 +/- 0.57 l *min(-1)) protocols. CO(2) output and blood PCO(2) were lower (p < 0.05), and V(E)/VCO(2) was higher (p < 0.05), above VT1 for SR compared to MR and FR protocols. No significant differences were observed among the protocols for VO(2), % VO(2)peak, V(E), plasma lactate ([La(-)]) and blood hydrogen ion concentration ([H(+)]), and heart rate (HR) values at VT1 or VT2. The work rate (WR) measured at VT1, VT2 and VO(2)peak increased (p < 0.05) with steeper ramp slopes. It was concluded that, in highly-trained cyclists, assessments of VT1 and VT2 are independent of ramp rate (10, 30, 50 W*min(-1)) when expressed as VO(2), % VO(2)peak, V(E), plasma [La(-)], blood [H(+)] and HR values, whereas VO(2)peak is lower during 10 W*min(-1) compared to 30 and 50 W*min(-1) ramp protocols. In addition, the WR measured at VT1, VT2 and VO(2)peak varies with the ramp slope and should be utilized cautiously when prescribing training or evaluating performance.

Does endurance training affect orthostatic responses in healthy elderly men?

PURPOSE: To investigate the effects and time course of endurance training on the regulation of heart rate (HR), arterial pressure (AP), norepinephrine (NE), and plasma volume (PV) during orthostatic stress in healthy elderly men. METHODS: Thirty-one healthy men (65--75 yr) were randomly allocated into endurance training (N = 20, EX) and control (N = 11, CON) groups. The EX group cycled 3 d x wk(-1) for 30 min at 70% VO(2peak) for 12 wk x VO(2peak) was determined on an electronically braked cycle ergometer, before training and after 4, 8, and 12 wk of endurance training. The immediate (initial 30 s), early steady-state (1 min), and prolonged (5, 10, 15 min) beat-by-beat HR and AP responses during 90 degrees head-up tilt (HUT) were measured at least 3 d after each VO(2peak) test. Spontaneous baroreflex slopes were determined by application of linear regression to sequences of at least three cardiac cycles in which systolic blood pressure (SBP) and R-R interval changed in the same direction. Venous blood was collected during 90 degrees HUT and analyzed for changes in plasma NE concentrations, as well as hematocrit and hemoglobin to determine changes in PV. RESULTS: Endurance training significantly (P < 0.01) increased VO(2peak) (mL x kg(-1) x min(-1)) in EX by 10 +/- 2%. The immediate, early steady-state, and prolonged HR and AP responses and spontaneous baroreflex slopes during 90 degrees HUT were not significantly different (P > 0.05) between EX and CON groups before or after 4, 8, or 12 wk of endurance training. No significant differences (P > 0.05) were observed between EX and CON groups for peak changes in PV during orthostasis before (-15.0 +/- 1.4% vs -11.9 +/- 1.3%) or after 4 (-12.2 +/- 1.0% vs -12.7 +/- 1.4%), 8 (-13.7 +/- 1.2% vs -12.4 +/- 0.7%), and 12 wk (-10.8 +/- 1.6% vs -10.6 +/- 0.6%) of endurance training, suggesting a similar stimulus presented by 90 degrees HUT in both groups. Peak changes in NE concentrations during HUT were similar (P > 0.05) between EX and CON groups before (119 +/- 23 pg x mL(-1) vs 191 +/- 36 pg x mL(-1)) and after 4 (139 +/- 29 pg x mL(-1) vs 146 +/- 25 pg x mL(-1)), 8 (114 +/- 32 pg x mL(-1) vs 182 +/- 41 pg x mL(-1)), and 12 wk (143 +/- 35 pg x mL(-1) vs 206 +/- 42 pg.mL-1) of endurance training. CONCLUSIONS: These data indicate that in healthy elderly men, improvements in VO(2peak) can occur without compromising the regulation of HR, AP, NE, and PV during orthostatic stress.

The effects of a liquid ethanol diet on nutritional status and fluid balance in the rat.

The liquid ethanol diet is a widely used method of ethanol administration. The purpose of this study was to evaluate fluid balance using a multitude of physiological parameters (electrolytes, osmolality, total serum proteins, fluid intake/output and body weight), during and after the introduction of liquid ethanol diet. Animals were randomized into four different dietary protocols (two control and two ethanol groups) and were placed in metabolic cages for 16 days. Serum electrolytes, as well as the above parameters, were measured before, during and 1 week after the introduction of 9% (v/v) ethanol-containing diet (Lieber-DeCarli: LD). After the first night on 9% (v/v) ethanol LD, animals had significantly decreased diet consumption, urine output and body weight. However, a major finding of this study was that, during the habituation phase, the electrolyte values remained within the normal range for rats and, in particular, serum sodium was not altered at any time point measured in this study. Based upon the findings from this study, it is recommended that body weight be carefully monitored as a measure of the animal's equilibration and physiological adaptation during the initiation of a liquid ethanol diet, since neither the serum sodium nor calculated osmolality values were changed. Our results also highlight the need to offer water to animals during the habituation phase of ethanol consumption. This is because ethanol rats that were offered water ad libitum lost less weight than groups that did not receive water ad libitum, despite consuming the same amount of LD diet.

Thermoregulatory responses to repeated warm water immersion in subjects who are paraplegic.

OBJECTIVE: To compare thermoregulatory responses to repeated warm water immersion (39 degrees C) between physically active subjects who are paraplegic or able-bodied in order to gain insight into rehabilitative and adaptive processes. METHODS: Five paraplegic (P) and six able-bodied (AB) males participated. VO2 peak was determined by open-circuit spirometry using a cycle ergometer (AB) and propelling a wheelchair on a motor driven treadmill (P). Subjects sat immersed to the nipple line in 39 degrees C water for 60 min for 5 consecutive days. Pre- and post-test measurements included heart rate (HR), oesophageal temperature (Tes), sweat onset and rate (dew point hygrometry). Venous blood was obtained before, and during immersion to estimate changes in plasma volume. RESULTS: The P group was older and lighter than AB group (P<0.05). VO2max, VCO2max and VE(max) were significantly greater in AB group. HR at rest and after 60 min immersion was not significantly different between the groups pre- or post-test. Tes significantly increased after 60 min immersion in both groups, at both pre- and post-testing sessions. Post-test Tes after 60 min immersion (AB) was significantly less than Tes after 60 min of immersion pre-test. The DeltaTes (Tes 60 min-Tes 0 min) was significantly higher in AB group than the P group at pre- but not post-testing. No significant changes in sweat onset or rate were found for the AB or P groups during the pre- or post testing sessions. Significant expansion of plasma volume occurred during immersion in both groups, pre- and post-immersion sessions. CONCLUSIONS: Repeated warm water immersion (39 degrees C) for 60 min per day for a total of 5 days did not produce a significant adaptive response in P group. In the AB group, Tes at the end of 60 min immersion was significantly lower after the adaptation period.

Cardiovascular regulation during head-up tilt in healthy 20-30-year-old and 70-75-year-old men.

This study compared the heart rate, finger arterial pressure (AP) and electromyographic (EMG) activity of selected anti-gravity muscles during the initial and prolonged phases of orthostatic stress in healthy young and older men. Beat-by-beat recordings of heart rate, finger systolic pressure, diastolic pressure and mean AP were made during supine rest and 5 min of 90 degrees head-up tilt (HUT) in 18 young (23+/-1 years) and 15 older (73+/-1 years) men. The EMG activity of the soleus, tibialis anterior and vastus medialis muscles was recorded. During the first 30 s following 90 degrees HUT (immediate response), the young men exhibited significant (P<0.05) decreases in finger systolic pressure, diastolic pressure and mean AP, followed by a sustained increase in finger AP during the 5 min following 90 degrees HUT (prolonged response). The immediate and prolonged finger AP and diastolic pressure responses were not significantly different (P>0.05) from the values at supine rest for the older men. The mean root mean square EMG activity of the soleus, tibialis anterior and vastus medialis muscles during 90 degrees HUT was not significantly different (P>0.05) from that at supine rest for either group. These results demonstrate that, when compared with healthy older men, young men show larger reductions in finger AP during the initial phase of orthostatic stress. However, during the prolonged phase of orthostatic stress, older men maintain resting finger AP, whereas young men demonstrate a reflex overshoot in finger AP. Finally, differences in lower-limb anti-gravity muscle activation do not account for the contrasting finger AP responses of healthy young and older men.

Norepinephrine and epinephrine responses during orthostatic intolerance in healthy elderly men.

In young individuals, orthostatic intolerance is associated with marked increases in plasma epinephrine (EPI) concentrations and attenuated rises in plasma norepinephrine (NE) concentrations. This study investigated the cardiovascular, EPI and NE responses of healthy elderly males during orthostatic stress. Twelve men (68 +/- 1 yr) with a recent history of orthostatic hypotension and who exhibited orthostatic intolerance (HYPO) during 90 degrees head-up tilt (HUT) were compared with 12 men (69 +/- 1 yr) without a history of orthostatic hypotension and who remained normotensive (NORMO) throughout 90 degrees HUT. Beat-by-beat recordings of heart rate (HR), mean (MAP), systolic (SBP), diastolic (DBP), and pulse (PP) pressures were made throughout 90 degrees HUT. Blood samples obtained during supine rest and 90 degrees HUT were analyzed for changes in EPI and NE concentrations, hematocrit, hemoglobin and plasma volume. Compared to supine rest, orthostatic intolerance was characterized by significant reductions (p < 0.0001) in MAP, SBP, DBP, and PP. The HR, MAP, SBP, DBP, and PP at the termination of 90 degrees HUT was significantly lower (p < 0.0001) for HYPO than NORMO. The 90 degrees HUT position resulted in significant increases (p < 0.01) in NE for both HYPO and NORMO, with the rise in NE significantly lower (p < 0.05) in HYPO. There were no differences between groups regarding EPI concentrations at the termination of 90 degrees HUT. These results suggest that the magnitude of arterial pressure (AP) reduction does not influence the EPI response during orthostasis in healthy elderly men. However, marked reductions in AP, leading to orthostatic intolerance, are associated with inadequate increases in NE in these individuals.

Plasma catecholamine and blood lactate responses to incremental arm and leg exercise.

PURPOSE AND METHODS: The present study was conducted to examine the pattern of plasma catecholamine and blood lactate responses to incremental arm and leg exercise. Seven untrained male subjects performed two incremental exercise tests on separate days in random order. One test consisted of 1-arm cranking (5W x 2 min(-1)), whereas the other exercise test was 2-leg cycling (20-25W x 2 min(-1)). Blood samples were obtained from the nonexercising arm during 1-arm cranking and from the same arm and vein during 2-leg cycling. Thresholds for blood lactate (T(La)), epinephrine (T(Epi)) and norepinephrine (T(NE)) were determined for each subject under both exercise conditions and defined as breakpoints when plotted as a function of power output. RESULTS: When the two modes of exercise were compared, T(La), T(Epi), and T(NE) were all significantly lower for 1-arm cranking than for 2-leg cycling (P < 0.01). During 1-arm cranking, T(La) (0.96 +/- 0.10 L x min(-1)), T(Epi) (1.02 +/- 0.07 L x min(-1)), and T(NE) (1.07 +/- 0.09 L x min(-1)) occurred simultaneously. During 2-leg cycling, T(La) (1.77 +/- 0.20 L x min(-1)), T(Epi) (1.74 +/- 0.17 L x min(-1)), and T(NE) (1.98 +/- 0.17 L x min(-1)) occurred at similar levels of VO2 and were not significantly different. The correlation observed between the VO2 measured at the T(La) and T(Epi) was 0.917 for arm and 0.929 for leg exercise (P < 0.001). The epinephrine concentration ([Epi]) obtained at the T(La) was not significantly different for arm (0.144 ng x mL(-1)) and leg (0.152 ng x mL(-1)) exercise. CONCLUSIONS: The breakpoint in plasma [Epi] shifted in an identical manner and occurred simultaneously with that of T(La) regardless of the mode of exercise (arm or leg). The Epi concentrations observed at the T(La) agree with those previously reported to produce a rise in blood lactate during Epi infusion at rest. These results support the hypothesis that a rise in plasma [Epi] may contribute to the breakpoint in blood lactate that occurs during incremental exercise.

VO2peak and the gas-exchange anaerobic threshold during incremental arm cranking in able-bodied and paraplegic men.

Resting energy expenditure, peak oxygen uptake (VO2peak) and the gas-exchange anaerobic threshold (Than) were measured during incremental arm cranking (15 W x min(-1)) in six able-bodied (AB) and six paraplegic (P) subjects. Only male subjects with traumatic spinal cord injuries in the area of the 10-12th thoracic segment were included in the P group. All AB and P subjects were physically active. Mean (SE) values for age and body mass were 28 (2) years and 78.9 (3.9) kg for the AB group and 32 (4) years and 70.8 (7.9) kg for the P group (P>0.05). Resting energy expenditure values were not found to be significantly different between AB [5.8 (0.2) kJ x min(-1)] and P [5.1 (0.3) kJ min(-1)] subjects. Mean VO2peak values were 29.3 (2.4) ml x kg(-1) min(-1) and 29.6 (2.2) ml x kg(-1) x min(-1) for the AB and P groups, respectively (P>0.05). Absolute oxygen uptake values measured at two gas-exchange anaerobic threshold (Than) were not significantly different between the two groups. However, the Than occurred at a significantly higher percentage of VO2peak in the P [58.9 (1.7)%] group than in the AB [50.0 (2.8)%] group (P<0.05). Moreover, respiratory exchange ratio (R) values obtained at the Than and at 15, 45, 60, 75 and 90 W of incremental exercise were significantly lower in the P group than in the AB group. Heart rates were significantly elevated at every submaximal work stage (15-120 W) in the P group compared to the AB group (P<0.05). These findings suggest that chronic daily wheelchair activity produces local adaptations in the functional upper-body musculature, which reduce glycogenolysis and increase the rate of lipid utilization (lower R) during arm exercise. These local adaptations may be in part responsible for the significantly higher Than observed for arm exercise in P subjects, even though VO2peak values were essentially the same for both groups.

Rectal and esophageal temperatures during upper- and lower-body exercise.

This study investigated the question: is core temperature measurement influenced by whether exercise involves predominantly upper- or lower-body musculature? Healthy men were allocated to three groups: treadmill ergometry (T) n = 4, cycle ergometry (C) n = 6 and arm crank ergometry (AC) n = 5. Subjects underwent an incremental exercise test to exhaustion on an exercise-specific ergometer to determine maximum/peak oxygen consumption (VO2max). One week later subjects exercised for 36 min on the same ergometer at approximately 65% VO2max while temperatures at the rectum (T(re)) and esophagus (T(es)) were simultaneously measured. The VO2max (1 x min(-1)) for groups T [4.76 (0.50)] and C [4.35 (0.30)] was significantly higher than that for the AC group [2.61 (0.24)]. At rest, T(re) was significantly higher than T(es) in all groups (P < 0.05). At the end of submaximal exercise in the C group, T(re) [38.32 (0.11) degrees C] was significantly higher than T(es) [38.02 (0.12) degrees C, P < 0.05]. No significant differences between T(re) and T(es) at the end of exercise were noted for AC and T groups. The temperature difference (T(diff)) between T(re) and T(es) was dissimilar at rest in the three groups; however, by the end of exercise T(diff) was approximately 0.2 degrees C for each of the groups, suggesting that at the end of steady-state exercise T(re) can validly be used to estimate core temperature.

Two isoforms of Drosophila dynamin in wild-type and shibire(ts) neural tissue: different subcellular localization and association mechanisms.

The temperature-sensitive mutations of the shibire (shi) gene in Drosophila cause endocytic arrest, resulting in neurotransmission block and paralysis at high temperatures. However, underlying mechanism for the defects is not yet known. We examined the subcellular distribution of dynamin, a product of the shi gene, by immunoblotting and immunocytochemical assays. Two isoforms of dynamin with apparent M(r) of 92 kD and 94 kD have been detected in wild-type and shi(n) adult neural tissue. The two isoforms were reproducibly associated with different subcellular fractions of head homogenates. The 94kD isoform is fractionated in the low speed (2.000 x g) pellet containing plasma membrane fragments, and the 92kD isoform in the high speed (130,000 x g) pellet. In this procedure, very little dynamin remained in the high speed supernatant fraction. The 94 kD isoform represents the majority (65-75%) of total dynamin and appears to be a peripheral membrane protein. It can be extracted from the low speed membrane pellet by high salt, Na2CO3 (pH 11) or Triton X-100 treatments. Extracted 94kD dynamin from both wild-type and mutant homogenates is able to reassociate with artificial phospholipid vesicles at both permissive and restrictive temperatures. Binding of the 94 kD dynamin to liposomes appears to be pH-dependent, varying most significantly within the physiological pH range, which may be functionally important. The 92 kD isoform cannot be released by high salt or Na2CO3 treatments and only a small fraction is released by Triton X-100, suggesting a different mechanism of association with cell structures. The distribution of the two isoforms is not altered by the presence of stabilized microtubules in homogenates. No apparent degradation or subcellular redistribution of mutant dynamin was detected in two shi(n) alleles after heat shock or block of the dynamin GTPase activity, suggesting that intracellular redistribution or degradation of mutant dynamin are not involved in the endocytosis arrest in these mutants. These observations resemble the effect of endocytosis arrest by GTP-gamma-S in rat brain synaptosomes (Takei et al., 1995), in which dynamin is trapped at the neck of invaginated pits but is absent in the clathrin-coated distal end undergoing internalization. Our finding that endocytosis arrest by shi(n) mutations and GTP-gamma-S do not lead to cumulation of dynamin in the low speed pellet fraction further suggests that the 94 kD isoform remains associated with the plasma membrane during coated vesicle pinch-off and that the two isoforms do not appear to correspond to different functional states of dynamin but are likely to be involved in separate cellular compartments within the membrane cycling pathway (e.g., the plasma membrane, endosomes, and endoplasmic reticulum).

Maximal physiological responses during arm cranking and treadmill wheelchair propulsion in T4-T6 paraplegic men.

The aim of the study was to compare the exercise responses during maximum wheelchair propulsion on a motor driven treadmill (TM) and maximum arm cranking (AC) in a homogenous group of nine paraplegic men with clinically complete spinal cord lesions between T4 and T6. The test order for each ergometer was random and time between the two ergometer tests was 3-7 days. All experiments were conducted in an air conditioned environment (23 degrees C DB, 18 degrees C WB). The highest VO2 recorded during the final minute of arm cranking (1.65 +/- 0.14 l min-1) and wheelchair propulsion on the treadmill (1.72 +/- 0.10 l min-1) was not significantly different. There were no significant differences in heart rate during the final minute of arm cranking (177 +/- 3 b min-1), and wheelchair propulsion on a motor driven treadmill (177 +/- 4 b min-1), nor were there any significant differences in minute ventilation (STPD) between AC (52 +/- 6.6 l min-1) and TM (56.1 +/- 4.8 l min-1). The VCO2 l min-1 for AC (2.00 +/- 0.20 l min-1) and TM (2.00 +/- 0.12 l min-1) was also not significantly different. The present study found that, unlike previous studies, no significant differences in VO2 (l min-1, ml kg-1 min-1) VE (l min-1), VCO2 (l min-1) or heart rate (b min-1) were found between the two modes of ergometry during the last minute of incremental exercise to exhaustion in a homogenous group of T4-T6 paraplegic men.(ABSTRACT TRUNCATED AT 250 WORDS)

The average daily energy expenditure of elderly males and females.

The aim of this study was to report on the average daily energy expenditure by elderly males and females in their normal day-to-day activities. The study was based on an analysis of data collected over six months from daily diary recording of activities. The subjects, 82 males and 93 females, were non-institutionalized volunteers with a mean age of 68 years. A multivariate analysis of variance indicated that there were no differences between males and females in total mean daily energy expended on Sporting activities. Females expended twice as much energy as males on Household Chores (F = 36.3,p < 0.001). Males expended over three times as much energy as females on gardening (F = 56.7, p < 0.001) and over seven times as much on Maintenance (F = 53.6, p < 0.001). There were also differences between males and females on energy expended while Walking (F = 6.1, p < 0.02) and on Miscellaneous activities (F = 6.3, p<0.05). It is concluded that sex stereotypical roles for activities required at younger ages are continued into old age. The implications of these findings for prescribing regular exercise in the elderly are discussed, indicating specific activities that might prove to be beneficial.

A cross-cultural assessment of perceived health problems in the elderly.

To study cross-cultural differences in perceived health problems in the elderly the Nottingham Health Profile (NHP) developed by Hunt et al. was administered to subjects from the People's Republic of China and Australia. The Australian stratum was further categorized according to cardiovascular status. Analyses of covariance (with age as the covariate) on each of the six subscales of the NHP yielded significant differences for 'Energy', 'Pain', 'Emotional reactions', 'Social isolation' and 'Physical mobility'. No differences were found for the 'Sleep' subscale. Through comparisons between the mean scores for the four strata and from normative data it is concluded that it is likely that the NHP is 'culture free' on the dimensions 'Energy', 'Pain', 'Emotional reactions', 'Social isolation' and 'Physical mobility'.

The effects of sauna on tetraplegic and paraplegic subjects.

Six tetraplegic (T) and 4 paraplegic (P) subjects underwent a 20-minute pre sauna phase (30 degrees C DB; 65% RH), and an up to 15-minute sauna (85 degrees C DB; less than 10% RH), followed by a 15 minute post sauna phase (30 degrees C DB; 65% RH). During all phases subjects wore a bathing suit and remained supine on a hospital trolley. Heart rate (HR) and blood pressure (BP) were recorded during all phases. Rectal temperature (Trec) was measured by a probe (AD590) inserted approximately 14 cm into the rectum. Oral temperature (Toral) also utilising (AD590) circuitry was recorded simultaneously with Trec. Skin temperature (Tsk) (AD590) was measured on the head, chest, right thigh and right calf. Forehead sweat rate (SR) was determined from dew point temperature (Tdp). A catheter was inserted into a dorsal hand or foot vein and venous blood was withdrawn at selected times and analysed for haemoglobin (Hb) and haematocrit (Hct), and the separated plasma was analysed for glucose (Glu), sodium (Na+), potassium (K+) and chloride (C1-). Venous blood sampled just prior to entering and just prior to leaving the sauna, was analysed for adrenalin (A) and noradrenalin (NA) using high performance liquid chromatography. For both groups HR rose significantly during the sauna with a significant decline in HR for the P group during the post sauna phase. There were no significant changes in systolic BP for either group. A significant decline in diastolic BP was found for the T group during the post sauna phase. There were no episodes of syncope.(ABSTRACT TRUNCATED AT 250 WORDS)

Perceived health problems in subjects with varying cardiovascular diagnoses.

To study perceived health problems in subjects with differing cardiovascular status, the Nottingham Health Profile (NHP) was administered to 210 subjects 55 years of age and over. Subjects were categorized as being cardiovascular "Normals," being hypertensive, having isolated coronary artery disease, or both being hypertensive and having coronary artery disease. An analysis of variance between the four cardiovascular strata on each of the six subscales of the NHP yielded significant differences between the groups on the subscales Pain, Physical Mobility, Energy, and Social Isolation. Subsequent conservative post hoc analyses of the group means on each of these variables indicated that the group with isolated coronary artery disease differed significantly from both the hypertensives and the Normals in Physical Mobility. For the Pain subscale the subjects with isolated coronary artery disease differed significantly from those with hypertension. There were no differences among the four cardiovascular groups in perceived health problems on the subscales Emotional Reactions and Sleep.