High-Intensity Walking Time Is a Key Determinant to Increase Physical Fitness and Improve Health Outcomes After Interval Walking Training in Middle-Aged and Older People

Low physical activity and depression are the prominent predictive factors for falling in older adults: the Birjand Longitudinal Aging Study (BLAS)

BACKGROUND

Falling in the older adults has many irreparable consequences, including hospitalization to long-term care centers and loss of independence, depression and social isolation, financial burden, and death. The present study was conducted to estimate the incidence of falls and their associated factors among community-dwelling older adults.

METHODS

This program is a population-based prospective cohort study (≥ 60 years) in Birjand City from 2019 to 2020. A total of 1418 participants were included in the study, and 1344 participants were analyzed according to the inclusion criteria. Thirty-nine risk factors were evaluated. Basic information included demographic information, lifestyle factors, general health and medical history, and mental and functional health.

RESULT

The incidence of falls among community-dwelling older adults in the previous approximately 24 months in the present study was 9.26% in women and 2.65% in men. In the multiple Cox proportional regression model based on fall risk factors, there was a strong significant relationship between male sex (HR = 0.37, CI = 0.21 to 0.64), being physically active (HR = 0.59, CI = 0.36 to 0.96), moderate-to-severe depression (HR = 2.97, CI = 1.47 to 6.01), severe depression (HR = 3.26, CI = 1.24 to 8.54), and high risk of falls according to the TUG test (HR = 1.73, CI = 1.10 to 2.72).

CONCLUSIONS

Inactivity and depression were recognized as important factors in falls in older adults. It is recommended for older adults to have an active lifestyle to prevent falls and to prioritize the diagnosis and treatment of depression in older adults. Women as a group at higher risk should be considered in prevention programs. In addition, the use of the TUG test to identify high-risk older adults should be considered.

Effects of interval-walking training on blood pressure in community-dwelling Japanese older adults

BACKGROUND

The hypotensive effects of high-intensity interval training have been reported; however, studies on older adults are few. This study aimed to examine whether interval-walking training (IWT), a home-based program of high-intensity interval training, reduces blood pressure (BP) levels when compared with a non-intervention group in community-dwelling older adults.

METHODS

An intervention study was conducted with 55 men (age, 75±5 years; IWT/control groups, N.=27/28) and 100 women (75±5 years; N.=47/53). The IWT regimen was as follows: fast (high-intensity) walking at 70-85% of the peak aerobic capacity and normal (light-intensity) walking at approximately 40% of the peak aerobic capacity for 3 min each, ≥5 times/walking day, and ≥4 days/week for 5 months. Systolic, diastolic, and mean arterial BPs (SBP, DBP, and MAP, respectively) were measured in the supine posture.

RESULTS

The mean baseline SBP/DBP was 132/78 mmHg in men and 131/72 mmHg in women. Five-month changes in SBP, DBP, or MAP did not significantly differ between the IWT and control groups in either sex. The weekly fast-walking time in the IWT group was negatively correlated with changes in DBP (Spearman's ρ=-0.383, P=0.049) and MAP (ρ=-0.444, P=0.021) only in men.

CONCLUSIONS

Though present findings did not indicate significant hypotensive effects of IWT in community-dwelling older adults, men with longer fast-walking times experienced greater BP decreases. Further studies with sufficient sample sizes are needed to determine the factors modulating the effects of the proposed training program.

Interval walking training in type 2 diabetes: A pilot study to evaluate the applicability as exercise therapy

There are few established easy-to-perform exercise protocols with evidence-based effects for individuals with type 2 diabetes (T2D). A unique exercise regimen, interval walking training (IWT), has been reported to be beneficial for improving metabolic function, physical fitness and muscle strength in adults of overall health. This pilot study aims to demonstrate descriptive statistics of IWT adherence and changes in various data before and after the intervention of IWT in adults with T2D, perform statistical hypothesis testing, and calculate effect sizes. We performed a single-arm interventional pilot study with IWT for 20 weeks. We enrolled 51 participants with T2D aged 20-80 years with glycohemoglobin (HbA1c) levels of 6.5-10.0% (48-86 mmol/mol) and a body mass index of 20-34 kg/m2, respectively. The target was 60 min/week of fast walking for 20 weeks. The participants visited the hospital and were examined at 4-week intervals during this period. Between the start of IWT and after 20 weeks, we measured and evaluated changes in glucose and lipid metabolism data, body composition, physical fitness, muscle strength, dietary calorie intake, and daily exercise calories. All included participants completed IWT, with 39% of them reaching the target length of fast walking over 1,200 minutes in 20 weeks. In the primary outcome, HbA1c levels, and in the secondary, lipid metabolism and body composition, no significant changes were observed except for high-density lipoprotein cholesterol (HDL-C) (from 1.4 mmol/L to 1.5 mmol/L, p = 0.0093, t-test). However, in the target achievement group, a significant increase in VO2 peak by 10% (from 1,682 mL/min to 1,827 mL/min, p = 0.037, t-test) was observed. Effect sizes were Cohen's d = 0.25 of HDL-C, -0.55 of triglyceride, and 0.24 of VO2 peak in the target achievement group, which were considered to be of small to medium clinical significance. These results could be solely attributed to IWT since there were no significant differences in dietary intake and daily life energy consumption before and after the study. IWT could be highly versatile and was suggested to have a positive effect on lipid metabolism and physical fitness. In future randomized controlled trial (RCT) studies, the detailed effects of IWT, focusing on these parameters, will be examined. Trial registration: This trial was registered with the Japanese University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR: Usefulness on interval walking training in patients with type 2 diabetes. 000037303).

Maria MT, Hori S, Morikawa M, Marito P, Kaneko N, Nohno K, Nose H, Masuki S, Ono T. Effects of Interval Walking Training on Oral Health Status in Middle-Aged and Older Adults: A Case-Control Study

The purpose of this study was to determine the effect of walking training "Interval Walking Training (IWT)" on oral health status. Participants were divided into two groups: an exercise intervention group and a non-intervention group (control). The intervention group consisted of 59 subjects (20 males, 39 females) aged 50 years or older who participated in the IWT program in Matsumoto from 2019 to April 2022. The control group consisted of 33 subjects (14 males and 19 females) aged 50 years or older who have visited Niigata University Medical and Dental Hospital and agreed to participate in the study. The intervention group underwent walking training (interval walking training) for at least 5-6 months. The walking training consisted of five sets of fast walking above 70% peak aerobic capacity for walking (VO₂peak) for 3 min, followed by 3 min of slow walking at ~40% VO₂ peak per day for more than four days/week. The oral health status was evaluated for the number of teeth, occlusal force, salivary occult blood, masticatory performance, and tongue pressure. A total of 57 participants were analyzed in the intervention group (18 males and 39 females, age: 66.7 ± 0.8 (mean ± S.E.) years) and 33 participants in the control group (14 males and 19 females, age: 74.5 ± 1.1 (mean ± S.E.) years). There were no significant differences in gender, salivary occult blood, tongue pressure, masticatory performance, or occlusal force between the two groups at the start of the intervention (p = 0.36, p = 0.48, p = 0.42, p = 0.58, and p = 0.08, respectively by unpaired t-test or χ² test). On the other hand, there were significant differences in age and BMI, with a trend toward lower age and higher BMI in the intervention group (p < 0.001 and p < 0.001, respectively, by unpaired t-test). In terms of rate of change, the intervention group showed a significant increase in occlusal force (F = 4.5, p = 0.04, ANCOVA) and a significant decrease in BMI (F = 7.3, p = 0.009, ANCOVA). No significant differences were observed in the other measured items. It was found that walking training in both middle-aged and older people does not only affect the physical aspect of weight loss but may help maintain and improve the occlusal force.

Effects of Yogurt Intake on Cardiovascular Strain during Outdoor Interval Walking Training by Older People in Midsummer: A Randomized Controlled Study

We examined whether post-exercise yogurt intake reduced cardiovascular strain during outdoor interval walking training (IWT) in older people during midsummer. The IWT is a training regimen repeating slow and fast walking at ~40% and ≥70% peak aerobic capacity, respectively, for 3 min each per set, ≥5 sets per day, and ≥4 days/wk. We randomly divided 28 male and 75 female older people (~73 yr), who had performed IWT ≥12 months, into a carbohydrate group (CHO-G) consuming jelly (45 g CHO, 180 kcal) and a yogurt group (YGT-G) consuming a yogurt drink (9.3 g protein, 39 g CHO, 192 kcal) immediately after daily IWT for 56 days while monitoring exercise intensity and heart rate (HR) with portable devices. We analyzed the results in 39 subjects for the CHO-G and 37 subjects for the YGT-G who performed IWT ≥ 4 days/wk, ≥60 min total fast walking/wk, and ≥4 sets of each walk/day. We found that the mean HR for fast walking decreased significantly from the baseline after the 30th day in the YGT-G (p < 0.03), but not in the CHO-G (p = 1.00). There were no significant differences in training achievements between the groups. Thus, post-exercise yogurt intake might reduce cardiovascular strain during outdoor walking training in older people.

Exercise suppresses mouse systemic AApoAII amyloidosis through enhancement of the p38 MAPK signaling pathway

Exercise interventions are beneficial for reducing the risk of age-related diseases, including amyloidosis, but the underlying molecular links remain unclear. Here, we investigated the protective role of interval exercise training in a mouse model of age-related systemic apolipoprotein A-II amyloidosis (AApoAII) and identified potential mechanisms. Mice subjected to sixteen weeks of exercise showed improved whole-body physiologic functions and exhibited substantial inhibition of amyloidosis, particularly in the liver and spleen. Exercise activated the hepatic p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway and the downstream transcription factor tumor suppressor p53. This activation resulted in elevated expression and phosphorylation of heat shock protein beta-1 (HSPB1), a chaperone that defends against protein aggregation. In amyloidosis-induced mice, the hepatic p38 MAPK-related adaptive responses were additively enhanced by exercise. We observed that with exercise, greater amounts of phosphorylated HSPB1 accumulated at amyloid deposition areas, which we suspect inhibits amyloid fibril formation. Collectively, our findings demonstrate the exercise-activated specific chaperone prevention of amyloidosis, and suggest that exercise may amplify intracellular stress-related protective adaptation pathways against age-associated disorders such as amyloidosis.

Ground reaction force and electromyograms of lower limb muscles during fast walking

Background

Physically active status is an important contributor to individual health. Walking is regarded as commonly accepted exercise for exercise promotion. Particularly, interval fast walking (FW), consisting of alternating between fast and slow walking speeds, has gained popularity from practical viewpoints. Although previous studies have determined the short- and long-term effects of FW programs on endurance capacity and cardiovascular variables, factors affecting these outcomes have not been clarified. In addition to physiological variables, understanding of mechanical variables and muscle activity during FW would be a help to understand characteristics of FW. In the present study, we compared the ground reaction force (GRF) and lower limb muscle activity between fast walking (FW) and running at equivalent speeds.

Method

Eight healthy men performed slow walking (45% of the maximum walking speed; SW, 3.9 ± 0.2 km/h), FW (85% of the maximum walking speed, 7.4 ± 0.4 km/h), and running at equivalent speeds (Run) for 4 min each. GRF and average muscle activity (aEMG) were evaluated during the contact, braking, and propulsive phases. Muscle activities were determined for seven lower limb muscles: gluteus maximus (GM), biceps femoris (BF), rectus femoris (RF), vastus lateralis (VL), gastrocnemius medialis (MG), soleus (SOL), and tibialis anterior (TA).

Results

The anteroposterior GRF was greater in FW than in Run during the propulsive phase (p < 0.001), whereas the impact load (peak and average vertical GRF) was lower in FW than in Run (p < 0.001). In the braking phase, lower leg muscle aEMGs were higher during Run than during SW and FW (p < 0.001). However, in the propulsive phase, soleus muscle activity was greater during FW than during Run (p < 0.001). aEMG of tibialis anterior was higher during FW than during SW and Run in the contact phase (p < 0.001). No significant difference between FW and Run was observed for HR and RPE.

Conclusion

These results suggest that the average muscle activities of lower limbs (e.g., gluteus maximus, rectus femoris, and soleus) during the contact phase were comparable between FW and running, however, the activity patterns of lower limb muscles differed between FW and running, even at equivalent speeds. During running, muscles were mainly activated in the braking phase related to impact. In contrast, during FW, soleus muscle activity during the propulsive phase was increased. Although cardiopulmonary response was not different between FW and running, exercise using FW might be useful for health promotion among individuals who cannot exercise at high-intensity.

Effects of arm cranking exercise on muscle oxygenation between active and inactive muscles in people with spinal cord injury

Objective: We investigated the effects of the incremental arm-cranking exercise (ACE) on tissue oxygen saturation (StO₂) between active and inactive muscles, and the relationship between peak oxygen uptake (VO_2peak) and changes in the StO₂ in inactive muscles.Design: Observational study.Setting: Community-based supervised intervention.Participants: The participants were individuals with motor and sensory complete spinal cord injury (complete SCI; n = 8) and motor complete but sensory incomplete SCI (incomplete SCI; n = 8), and able-bodied (AB) individuals (n = 8) matched for age, height, and body mass index.Intervention: The ACE was performed at a rate increasing by 10 watts min^-1 until exhaustion.Outcome Measures: VO_2peak, heart rate (HR), and StO₂.Results: While VO_2peak was similar among the groups, peak HR was significantly higher in both SCI groups than in the AB (P < 0.05). In active muscles (biceps brachii), no differences in the StO₂ were observed among the groups (P > 0.05). In inactive muscles (vastus lateralis), the StO₂ in the AB and the incomplete SCI began to decrease at approximately 40% of the peak work rate; however, they remained unchanged in the complete SCI. The reductions in StO₂ in the AB were significantly greater than in the incomplete SCI.Conclusions: These results suggest that sympathetic vasoconstriction occurred in the incomplete SCI and AB, although it did not occur in the complete SCI, probably due to a reduction in sympathetic nerve activity. Sympathetic vasoconstriction in inactive muscles may not contribute to an individual's VO_2peak regardless of their group.

Exercise Training Protocols to Improve Obesity, Glucose Homeostasis, and Subclinical Inflammation

The global pandemics of obesity and sedentarism are associated with poor quality of life and increased risks for development of inflammatory chronic diseases, including type 2 diabetes, cardiovascular diseases, and cancer. Physical activity is considered as an antidote to counteract the development of chronic sterile inflammatory diseases. Thus, we review the most promising exercise training protocols for promoting weight loss, improving glucose homeostasis, and reducing inflammation. We discuss the advantages and disadvantages of moderate-intensity continuous aerobic training, high-intensity aerobic training, and combined (aerobic + resistance) training. Our aim with this chapter is to provide evidence and guidance for choosing the most appropriate protocols of exercise training according to the goals of the patient.

Effects of 5-aminolevulinic acid with iron supplementation on respiratory responses to graded cycling and interval walking training achievement in older women over 75 yrs

BACKGROUND

Exercise training above a given intensity is necessary to prevent age-associated physical disability and diseases; however, the physical and psychological barriers posed by deteriorated physical fitness due to aging may hinder older people from performing daily exercise training. Because 5-aminolevulinic acid (ALA), a precursor of heme, reportedly improves mitochondrial function, we examined whether ALA, combined with sodium ferrous citrate (SFC) for enhancement, improved aerobic capacity and voluntary exercise training achievement in older women aged over 75 yrs.

METHODS

The study was conducted using a placebo-controlled, double-blind crossover design. Fifteen women aged ~78 yrs. with no exercise habits underwent two trials for 7 days each where they performed interval walking training (IWT), repeating fast and slow speeds of walking for 3 min each, at >70% and at ~40% of peak aerobic capacity for walking, respectively, with ALA+SFC (100 and 115 mg/day, respectively) or placebo supplement intake (CNT), with a 12-day washout period. Before and after each trial, subjects underwent a graded cycling test while having their oxygen consumption rate (V·O₂), carbon dioxide production rate (V·CO₂), and plasma lactate concentration ([Lac^-]_p) measured. Furthermore, during the supplement intake period, exercise intensity for IWT was measured by accelerometry.

RESULTS

In ALA+SFC, the increases in V·O₂ and V·CO₂ during the graded cycling test were attenuated (both, P < 0.01) with a 13% reduction in [Lac^-]_p (P = 0.012) while none of these attenuated responses occurred in CNT (all, P > 0.46). Furthermore, energy expenditure and time during fast walking for IWT were 25% (P = 0.032) and 21% (P = 0.022) higher in ALA+SFC than in CNT.

CONCLUSION

Thus, ALA+SFC supplementation improved aerobic capacity and thus increased fast-walking training achievement in older women.

Internet of Things (IoT) System and Field Sensors for Exercise Intensity Measurements

Although exercise training according to individual peak aerobic capacity ( V ˙ o_2peak ) has been recommended at all ages, sensors available in the field are limited. The most popular sensors in the field are pedometers, but they cannot be used to monitor exercise intensity. Instead, although heart rate (HR) monitors are broadly available in the field to estimate exercise intensity, HR responses to exercise vary by individual according to physical fitness and environmental conditions, which hinders the precise measurement of energy expenditure. These issues make it difficult for exercise physiologists to collaborate with geneticists, nutritionists, and clinicians using the internet of things (IoT). To conquer these problems, we have developed a device that is equipped with a triaxial accelerometer and a barometer to measure energy expenditure during interval walking training (IWT) in the field with inclines. IWT is a training regimen to repeat fast and slow walking for 3 min each, equivalent to greater than 70% and approximately 40% of individual V ˙ o_2peak , respectively. Additionally, we developed an IoT system that enables users to receive instructions from trainers according to their walking records even if they live far away. Since the system is available at low cost with minimum personnel, we can investigate any factors affecting the adherence to and effects of IWT in a large population for a long period. This system was also used to verify any effects of nutritional supplements during IWT and to examine the value of applying IWT to clinical medicine. © 2020 American Physiological Society. Compr Physiol 10:1207-1240, 2020.

Combined high-intensity interval training and green tea supplementation enhance metabolic and antioxidant status in response to acute exercise in overweight women

Thirty sedentary overweight women were randomly assigned to three groups (n = 10), including HIIT + green tea, HIIT + placebo and green tea. The training program included 3 sessions/week HIIT while the supplement consuming groups took 3 * 500 mg of green tea tablets/day for 10 weeks. Results indicated that 10 weeks of HIIT and green tea meaningfully pronounced baseline serum levels of SIRT1 (P ≤ 0.0001), PGC-1α (P ≤ 0.0001) and CAT (P ≤ 0.0001). In addition, significant increase was observed in three indicators in HIIT + green tea group in comparison with two other research groups. Further, the responses of SIRT1 (P ≤ 0.01) and CAT (P ≤ 0.002) increased significantly to second acute exercise in all three groups. The combination of HIIT and green tea consumption may induce increasing SIRT1 and CAT in response to acute exercise and can improve antioxidant system, body composition and VO2 max results rather than green tea and training alone, in young sedentary overweight women.