Walking-Induced Fatigue Leads to Increased Risk in Older Adults

Background- For older adults, falls are a serious health problem, with more than 30% of people older than 65 suffering a fall at least once a year. One element often overlooked in the assessment of falls is whether a person\u27s balance, walking ability, and overall falls risk is affected by performing activities of daily living such as walking. Objective- This study assessed the immediate impact of incline walking at a moderate pace on falls risk, leg strength, reaction time, gait, and balance in 75 healthy adults from 30 to 79 years of age. Subjects were subdivided into 5 equal groups based on their age (group 1, 30-39 years; group 2, 40-49 years; group 3, 50-59 years; group 4, 60-69 years; group 5, 70-79 years). Methods- Each person\u27s falls risk (using the Physiological Profile Assessment), simple reaction time, leg strength, walking ability, and standing balance were assessed before and after a period of incline walking on an automated treadmill. The walking task consisted of three 5-minute trials at a faster than preferred pace. Fatigue during walking was elicited by increasing the treadmill incline in increments of 2 degrees (from level) every minute to a maximum of 8 degrees. Results- As predicted, significant age-related differences were observed before the walking activity. In general, increasing age was associated with declines in gait speed, lower limb strength, slower reaction times, and increases in overall falls risk. Following the treadmill task, older adults exhibited increased sway (path length 60-69 years; 10.2 ± 0.7 to 12.1 ± 0.7 cm: 70-79 years; 12.8 ± 1.1 to 15.1 ± 0.8 cm), slower reaction times (70-79 years; 256 ± 6 to 287 ± 8 ms), and declines in lower limb strength (60-69 years; 36 ± 2 to 31 ± 1 kg: 70-79 years; 32.3 ± 2 to 27 ± 1 kg). However, a significant increase in overall falls risk (pre; 0.51 ± 0.17: post; 1.01 ± 0.18) was only seen in the oldest group (70-79 years). For all other persons (30-69 years), changes resulting from the treadmill-walking task did not lead to a significant increase in falls risk. Conclusions: As most falls occur when an individual is moving and/or fatigued, assessing functional properties related to balance, gait, strength, and falls risk in older adults both at rest and following activity may provide additional insight

Use of Heart Rate Reserve and Rating of Perceived Exertion to Prescribe Exercise Intensity in Diabetic Autonomic Neueropathy

Objective- Individuals with diabetic autonomic neuropathy (DAN) exhibit an increased resting heart rate but depressed maximal heart rate. Thus, the purpose of this study was to examine the validity of using either percent of heart rate reserve (HRR) or a rating of perceived exertion (RPE) scale to prescribe exercise intensity in diabetic individuals both with and without DAN. Research Design and Methods-The subjects consisted of 23 individuals with type 2 diabetes, ages 45-75 years, with (DAN; n=13) or without (No DAN; n=10) clinical signs of DAN, as assessed by heart rate variability using the expiration-to-inspiration ratio of the R-R interval. Peak aerobic capacity was determined using a graded protocol on a cycle ergometer, with RPE, heart rate, and Vo2 values recorded at each Stage. Results-The subjects were similar with the exception of depressed autonomic function in DAN subjects. Peak respiratory exchange ratio values were significantly higher (P\u3c0.05) in the DAN group (1.08 +/- 0.02 vs. 1.02 +/- 0.01 in No DAN subjects), although DAN subjects exhibited a significantly lower (P\u3c0.05) peak exercise heart rate. A similarly highly linear relationship between %HRR and percent Vo2 reserve (Vo2R) existed for both groups (r=0.98). A similar slightly weaker relationship (r=0.94) was found between RPE and %Vo2R. Conclusions-in conclusion, in diabetic individuals, %HRR provides an accurate prediction of %VO2R and can be used to prescribe and monitor exercise intensity, regardless of the presence of DAN. The RPE scale is, also a valid, albeit slightly less accurate, method to monitor exercise intensity in diabetic individuals

Balance Training Reduces Falls Risk in Older Individuals With Type 2 Diabetes

OBJECTIVE - This study assessed the effects of balance/strength training on falls risk and posture in older individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS - Sixteen individuals with type 2 diabetes and 21 age-matched control subjects (aged 50-75 years) participated. Postural stability and falls risk was assessed before and after a 6-week exercise program. RESULTS - Diabetic individuals had significantly higher falls risk score compared with control subjects. The diabetic group also exhibited evidence of mild-to-moderate neuropathy, slower reaction times, and increased postural sway. Following exercise, the diabetic group showed significant improvements in leg strength, faster reaction times, decreased sway, and, consequently, reduced falls risk. CONCLUSIONS - Older individuals with diabetes had impaired balance, slower reactions, and consequently a higher falls risk than age-matched control subjects. However, all these variables improved after resistance/balance training. Together these results demonstrate that structured exercise has wide-spread positive effects on physiological function for older individuals with type 2 diabetes

Melatonin Supplementation Improves Glycemic Control While Lowering Oxidative Stress in Type 2 Diabetes

The purpose of this investigation was to evaluate the effect of melatonin on glycemic control and oxidative stress (OS) in adults with type 2 diabetes (T2D). Fourteen subjects with T2D (10 female, 4 male; 52.5 ± 5.0 years) were randomly assigned to melatonin (MEL) or placebo groups (PLA) for 42 days, in a crossover design. Subjects ingested 10 mg of MEL or an identical placebo (PLA) 30 minutes prior to sleep. Fasting blood draws occurred at baseline, 42 days, and 84 days. Plasma malondialdehyde, a marker of OS, significantly decreased on MEL (-6.25±2.10 nmol/ml) compared to PLA (0.72±3.30, p=0.028). The change in hemoglobin A1c showed a total improvement of 0.33% following MEL supplementation compared to PLA (-0.24±0.23 % for MEL vs. 0.09±0.21 % for PLA, p=0.01), although no significant changes were noted in fasting plasma glucose or lipid levels. Daily melatonin may diminish OS and enhance glycemic control in adults with T2D

A Comparison of Screening Tools for the Early Detection of Peripheral Neuropathy in Adults With and Without Type 2 Diabetes

Objective. Examine the effectiveness of the 128 Hz tuning fork, two monofilaments, and Norfolk Quality of Life Diabetic Neuropathy (QOL-DN) questionnaire as tools for the early detection of diabetic peripheral neuropathy (DPN) in overweight, obese, and inactive (OOI) adults or those who have prediabetes (PD) or type 2 diabetes (T2D). Research Design and Methods. Thirty-four adults (mean age 58.4 years +/- 12.1) were divided by glycemia (10 OOI normoglycemic, 13 PD, and 11 T2D). Sural nerves were tested bilaterally with the NC-stat DPNCheck to determine sural nerve amplitude potential (SNAP) and sural nerve conduction velocity (SNCV). All other testing results were compared to SNAP and SNCV. Results. Total 1 g monofilament scores significantly correlated with SNAP values and yielded the highest sensitivity and specificity combinations of tested measures. Total QOL-DN scores negatively correlated with SNAP values, as did QOL-DN symptoms. QOL-DN activities of daily living correlated with the right SNAP, and the QOL-DN small fiber subscore correlated with SNCV. Conclusions. The 1 g monofilament and total QOL-DN are effective, low-cost tools for the early detection of DPN in OOI, PD, and T2D adults. The 128 Hz tuning fork and 10 g monofilament may assist DPN screening as a tandem, but not primary, early DPN detection screening tools

Cardiac Autonomic Neuropathy in Diabetes: A Predictor of Cardiometabolic Events

Autonomic nervous system (ANS) imbalance manifesting as cardiac autonomic neuropathy in the diabetic population is an important predictor of cardiovascular events. Symptoms and signs of ANS dysfunction, such as resting heart rate elevations, diminished blood pressure responses to standing, and altered time and frequency domain measures of heart rate variability in response to deep breathing, standing, and the Valsalva maneuver, should be elicited from all patients with diabetes and prediabetes. With the recognition of the presence of ANS imbalance or for its prevention, a rigorous regime should be implemented with lifestyle modification, physical activity, and cautious use of medications that lower blood glucose. Rather than intensifying diabetes control, a regimen tailored to the individual risk of autonomic imbalance should be implemented. New agents that may improve autonomic function, such as SGLT2 inhibitors, should be considered and the use of incretins monitored. One of the central mechanisms of dysfunction is disturbance of the hypothalamic cardiac clock, a consequence of dopamine deficiency that leads to sympathetic dominance, insulin resistance, and features of the metabolic syndrome. An improvement in ANS balance may be critical to reducing cardiovascular events, cardiac failure, and early mortality in the diabetic population

A Comparison of Neuropathy Quality of Life Tools: Norfolk QOL-DN, PN-QOL-97, and NeuroQOL-28

Aims To explore the effectiveness of the Norfolk QOL-DN (QOL-DN), PN-QOL-97, and NeuroQOL-28 as tools for early detection of diabetic peripheral neuropathy in overweight, obese, and inactive (OOI), prediabetes (PD), and type 2 diabetes (T2D) individuals. Methods Thirty-four adults were divided by A1C [(10 OOI, 13 PD, and 11 T2D] and the sural nerves were tested bilaterally via NC-Stat DPN Check, conducting a sural nerve conduction study (NCS). Participants were individually timed, filling out questionnaires (QOL-DN, NeuroQOL-28, and PN-QOL-97) at a self-selected pace. Data were analyzed and compared to NCS findings to determine the best instrument for early neuropathy detection, usability in screening settings, and application for individuals with OOI, PD, and T2D. Results Abnormal NCS results were obtained from 27 individuals, of which 25 were bilateral and symmetrical. Confirmed DSPN criteria were met for 24, and 1 case met criteria for subclinical neuropathy. Normal NCS findings, reported symptoms, and reduced bilateral sensation were found in 7 cases. The QOL-DN and NeuroQOL-28 significantly predict neuropathy criteria in OOI, PD, and T2D subjects. Analyses revealed the QOL-DN as the quickest for completion (M=5.17; SD=1.83), followed by the NeuroQOL-28 (M=5.58; SD=3.56), and the PN-QOL-97 (M=13.23; SD=3.606). Conclusions The QOL-DN and NeuroQOL-28 are valid early screening measures for DPN detection. Time completion studies revealed that the QOL-DN and NeuroQOL-28 may be used as excellent short screening measures, completed in approximately 6 minutes or less, with reasonable scoring for both. The NeuroQOL-28 is a better fit for immediate feedback, time constraints, or limited staff. Future investigations should evaluate these tools for detection in DPN-prone individuals and in subclinical populations screenings

Effects of 8 Weeks of Flexibility and Resistance Training in Older Adults With Type 2 Diabetes

(First paragraph) Flexibility is often downplayed as unimportant to fitness. However, flexibility training is imperative to maintain full range of motion (ROM) of joints, particularly in individuals with type 2 diabetes, who may experience limited joint mobility due to glycation of joint structures (1). Maladies such as “frozen shoulder” are common complaints in type 2 diabetes (2)