Treadmill Research Articles

A unified heart rate control approach for cycle ergometer and treadmill exercise

ObjectiveTo develop a unified heart rate (HR) control approach for cycle ergometer (CE) and treadmill (TM) exercise, and to empirically compare the common controller's performance between the CE and TM. MethodsThe control method used frequency-domain shaping of the input-sensitivity function to address rejection of disturbances arising from broad-spectrum heart rate variability (HRV). A single controller was calculated using an approximate, nominal linear plant model and an input-sensitivity bandwidth specification. Fifty HR control tests were executed using the single controller: 25 healthy male participants each did one test on the CE and one on the TM. ResultsThere was no significant difference in mean root-mean-square HR tracking error: 3.10 bpm ± 0.68 bpm and 2.85 bpm ± 0.75 bpm (mean ± standard deviation, bpm = beats/min); CE vs. TM; p = 0.13. But mean normalised average control signal power was significantly different: 1.59 bpm2 ± 0.27 bpm2 vs. 1.36 bpm2 ± 0.28 bpm2; CE vs. TM; p = 3.5 × 10−4. Conclusion and significanceThe lower values for RMS tracking error and control signal power for the TM point to decreasing HRV intensity with increasing HR, because, in order to match perceived exertion for the two modalities, mean HR for the TM was set 20 bpm higher than for the CE. These HR-intensity-dependent differences in HRV are consistent with previous observations in the literature. The unified HR control approach for CE and TM exercise gave accurate, stable and robust performance in all tests, thus lending support to the concept that HRV disturbance rejection is the main issue in HR control design.

The effect of test modality on dynamic exercise biomarkers in children, adolescents, and young adults.

Cardiopulmonary exercise testing (CPET) modalities, treadmill (TM), and cycle ergometer (CE), influence maximal gas exchange and heart rate (HR) responses. Little is known regarding CPET modality effect on submaximal biomarkers during childhood and adolescence. Ninety‐four healthy participants (7–34 y.o., 53% female) performed TM and CE CPET to address two major gaps: (1) the effect of modality on submaximal CPET biomarkers, and (2) estimation of work rate in TM CPET. Breath‐by‐breath gas exchange enabled calculation of linear regression slopes such as V˙O2/ΔHR and ΔV˙E/ΔV˙CO2. Lean body mass (LBM) was measured with dual X‐ray absorptiometry. We tested a novel TM CPET estimate of work rate based on TM velocity2, incline, and body mass (VIM). Like the linear relationship between V˙O2 and work rate in CE CPET, V˙O2 increased linearly with TM VIM. TM ΔV˙O2/ΔHR was highly correlated with CE (r = 0.92), and each increased substantially with LBM (P < 0.0001 for TM and CE). ΔV˙O2/ΔHR was to a small (~8.7%) but significant extent larger in TM (1.6 mL/min/beat, P = 0.04). In contrast, TM and CE ΔV˙E/ΔV˙CO2 decreased significantly with LBM, supporting earlier observations from CE CPET. For both CE and TM, males had significantly higher ΔV˙O2/ΔHR but lower ΔV˙E/ΔV˙CO2 than females. Novel TM CPET biomarkers such as ΔVIM/ΔHR and ∆V˙O2/ΔVIM paralleled effects of LBM observed in CE CPET. TM and CE CPET submaximal biomarkers are not interchangeable, but similarly reflect maturation during critical periods. CPET analysis that utilizes data actually measured (rather than estimated) may improve the clinical value of TM and CE CPET.

Acute Cardiometabolic Responses to Multi-Modal Integrative Neuromuscular Training in Children.

Integrative neuromuscular training (INT) has emerged as an effective strategy for improving health- and skill-related components of physical fitness, yet few studies have explored the cardiometabolic demands of this type of training in children. The aim of this study was to examine the acute cardiometabolic responses to a multi-modal INT protocol and to compare these responses to a bout of moderate-intensity treadmill (TM) walking in children. Participants (n = 14, age 10.7 ± 1.1 years) were tested for peak oxygen uptake (VO2) and peak heart rate (HR) on a maximal TM test and subsequently participated in two experimental conditions on nonconsecutive days: a 12-min INT protocol of six different exercises performed twice for 30 s with a 30 s rest interval between sets and exercises and a 12-min TM protocol of walking at 50% VO2peak. Throughout the INT protocol mean VO2 and HR increased significantly from 14.9 ± 3.6 mL∙kg−1∙min−1 (28.2% VO2 peak) to 34.0 ± 6.4 mL∙kg−1∙min−1 (64.3% VO2 peak) and from 121.1 ± 9.0 bpm (61.0% HR peak) to 183.5 ± 7.9 bpm (92.4% HR peak), respectively. While mean VO2 for the entire protocol did not differ between INT and TM, mean VO2 and HR during selected INT exercises and mean HR for the entire INT protocol were significantly higher than TM (all Ps ≤ 0.05). These findings suggest that INT can pose a moderate to vigorous cardiometabolic stimulus in children and selected INT exercises can be equal to or more metabolically challenging than TM walking.

Comparison of Maximal Aerobic Capacity Between the Treadmill and a Skiing Ergometer

Cross-country skiing is known to be an extremely aerobically demanding sport. Therefore, the use of a skiing ergometer (ie. SkiErg) to replicate similar aerobic training is increasing in use in lab and fitness settings. The SkiErg is widely used in gyms, research laboratories, and rehabilitation centers, and provides a low impact and total body cardiovascular and muscular endurance workout. Technique for training on the SkiErg can be quickly learned and adapted for immediate use by most individuals. Because of its lower cost and minimal required floor space, this piece of fitness equipment can be used at almost any location for exercise and training. Due to the benefits, convenience, and accessibility, the SkiErg may be a viable alternative max or peak graded exercise test (GXT) mode. To the best of the researchers’ knowledge, a comparison of aerobic capacity between a SkiErg and treadmill has not been assessed. PURPOSE: To compare treadmill (TM) VO2max values vs. those elicited from a SkiErg (SE) GXT. METHODS: Descriptive data (HT. = 176.1 + 8.2 cm, WT. = 80.5 + 10.1 kg, BF% = 15.1 + 5.8%, age = 22.7 + 2.4 yrs) was measured for 21 averagely fit college-age males. In a counterbalanced order and separated by 72 hours of rest, each subject completed 2 GXT protocols to the point of volitional exhaustion on a TM and SE. Max or peak values for VO2, HR, VE, and RER were compared between TM and SE using a Paired-Samples t-Test with an alpha level at p < 0.05. Peak RPE was compared using a Wilcoxon Signed Rank Test. RESULTS: TM was significantly greater than SE in regard to mean VO2max (51.1 ± 5.0 vs 44.5 ± 3.8 ml/kg/min, p < 0.01), HR (191 ± 11 vs 186 ± 10 bpm, p < 0.01), and RPE (19.6 + 2.2 vs 18.3 + 1.6, p = 0.039). TM was not significantly greater than SE regarding RER (1.2 + 0.0 vs 1.2 + 0.1, p = 0.862) or VE (146.2 + 16.5 vs 144.3 + 21.5 L/min, p = 0.614). CONCLUSIONS: The TM appears to yield higher max values for VO2, HR, RER, VE, and RPE values compared to SE in college-age males. Although TM elicited higher values than SE, SE VO2peak was only 15% lower than values measured from TM. This percent difference is comparable to other currently accepted alternative forms of aerobic capacity testing such as leg and arm cycle ergometers. Future studies should assess how gender, protocol variations, SE technique, or various athletic populations may impact VO2 values during a peak SE GXT.

Effect of Treadmill vs. Recumbent Cross Trainer on Gait and Leg Electromyography after Chronic Stroke

A recumbent cross trainer (RCT) relies on similar neural networks as gait. Therefore, neurologically impaired individuals may improve walking ability after exercise on the RCT. PURPOSE: The purpose of this investigation was to compare the effects of the RCT and Treadmill (TM) on intra-exercise electromyography and post-exercise spatial-temporal gait parameters. METHODS: 34 participants were divided into two groups; stroke (CVA) (10 ± 5 years post-CVA) and age and sex-matched control. Participants completed two 5-minute exercise bouts on both the RCT and TM at an RPE based self-selected cadence. Intra-exercise Mean electromyography (mEMG) values were normalized to maximum voluntary contraction and were recorded bilaterally at the rectus femoris, vastus medialis oblique, semitendinosus, tibialis anterior, medial gastrocnemius, and soleus. Change in joint range of motion was calculated (maximum-minimum degree; ∆ROM) from wireless goniometer measures at the hip, knee, and ankle. Gait parameters were evaluated by the Wireless Gait Assessment Tool (WiGAT) immediately following each exercise bout (3 x 10m walk). HR and BP were monitored to ensure the return to pre-exercise levels. RESULTS: Stroke (n = 15) and healthy (n = 19) did not differ in age (Mdn: 66 years vs. 57 years, respectively) or BMI (Stroke: M = 27.02, SD = 4.57 vs. Healthy: M = 26.46, SD = 4.63), p > .05. Healthy participants were stronger at all joints, p < .025. Preferred TM speed was faster in the healthy condition despite no statistical difference in RPE, p < .05. RCT average steps per minute did not differ between the conditions, p >.05. RPE did not differ between groups or across exercise modes. The TM elicited a higher mEMG on a majority of the studied muscles in both populations, p <.025. TM demonstrated an increased ∆ROM in the R knee and both ankles in the healthy population, p < .025. There were no statistical differences between the TM and RCT in the CVA’s ∆ROM. WiGAT determined the RCT decreased the stance percentage (%) and increased swing % on the non-affected leg, p < .05. Neither exercise mode modulated the affected-side stance %, affected-side swing %, double support time or bilateral (affected vs. non-affected) stride length, p>.05. CONCLUSION: Five minute RCT intervention improved non-affected side gait parameters in a chronic CVA population.

Feasibility Of Overground High-intensity Interval Training (hit) In Persons With Chronic Stroke

Evidence suggests that treadmill (TM) HIT can be safe and effective as a rehabilitation tool in persons with stroke. However, translation to overground walking can be limited and no studies have tested overground (OG) HIT. PURPOSE: To compare training speeds and HR responses for TM HIT and OG HIT in persons with chronic stroke. METHODS: Ten subjects (mean ± SD) 59.8 ± 6.8 years old and 2.4 ± 1.7 years post stroke with comfortable gait speed of 0.41 ± 0.35 m/s and fast gait speed of 0.56 ± 0.56 m/s participated and passed a symptom-limited GXT. Subjects performed 12 sessions of HIT over 4 weeks, alternating short and long interval HIT sessions. Both HIT protocols included 10 minutes of overground HIT (OG1), then 20 minutes of treadmill HIT, followed by another 10 minutes of overground HIT (OG2). Short interval HIT involved 30s bursts at maximum safe speed and 30-60s rest periods. Long interval HIT involved 4-min bursts at ~90% of peak heart rate (HRpeak) from the GXT and 3-min recovery periods at ~70% HRpeak. Variables recorded included gait training speeds and mean and max heart rate. OG1 and OG2 data were combined to control for warm up and cardiovascular drift effects. Mixed effects models were used to compare TM and OG exercise responses, while accounting for repeated measures from the same participant. RESULTS: All participants completed 12 sessions and no serious adverse events occurred. With the short interval protocol, OG HIT elicited significantly slower gait training speeds than TM HIT (0.75 vs. 0.90 m/s, p<0.0001), with lower mean HR (78.4 vs 82.9 %HRpeak, p<0.0001) and max HR (89.2 vs. 97.0 %HRpeak, p<0.0001). With the long interval protocol, OG HIT elicited significantly faster gait training speeds than TM HIT (0.66 vs. 0.51 m/s, p<0.0001) with similar mean HR (81.2 vs 81.9 %HRpeak, p=0.10) and lower max HR (92.7 vs. 95.8 %HRpeak, p<0.0001). CONCLUSIONS: OG HIT appears to be reasonably feasible and safe in chronic stroke. Mean OG HIT speeds were 34% and 18% faster than baseline fastest gait speed for short and long interval HIT, respectively. For short interval HIT, it may be optimal to combine the task specificity of overground training with the higher speeds and intensity of treadmill training. For long interval HIT, treadmill training does not appear to provide the same intensity benefit and overground training alone may be superior.

Differences In Indoor, Outdoor, And Treadmill Walking In Healthy Young Adults

The ability to ambulate within one’s environment is an important skill for everyday life, however, traditional methods of assessing gait involve walking in controlled settings that may not represent performance in real-world environments. Laboratory and clinically-based quantitative gait assessments are often conducted in a sterile and uniform environment and treadmill walking assessments, used to collect a large amount of walking data, are conducted with an externally driven speed and fixed environment. As such, gait demonstrated in these assessments may not reflect gait performance in the real-world environment. PURPOSE: To compare gait behavior among overground indoor, outdoor, and treadmill walking in healthy adults. METHODS: 16 healthy young adults (5M, 11F, 21±2yrs) performed three walking trials (500m each) at a self-selected pace: indoors around a gymnasium (IN), outdoors along a sidewalk (OUT), and on a treadmill (TM). Data were collected using wearable sensors and the following variables were calculated for each trial: cadence, gait velocity, double support %, step time, stride length. Two repeated-measures MANOVAs were used to compare mean values and variability (standard deviation (SD)) across conditions. RESULTS: Significant differences were found across the conditions for both mean values (Λ*=.038, F(10,6)= 15.18, p=.002), and variability (Λ*=.037, F(10,6)= 15.41, p=.002). Univariate tests showed differences in mean values between all three conditions for cadence, gait velocity, step time, and stride length (p<.003), and greater double support time in the TM condition than the IN or OUT conditions (p=.006). Univariate tests for variability measures failed to detect statistically significant differences (p>.01). The TM condition had a lower gait velocity SD than IN or OUT (p=.001). CONCLUSION: Healthy young adults adopt different walking strategies while walking indoors, outdoors, and on a treadmill.

Quantification of coronary artery disease using different modalities of cardiopulmonary exercise testing

BackgroundThis study examined the accuracy of cardiopulmonary exercise testing (CPET) on a treadmill (TM) and recumbent ergometry (RE) in the predicting coronary artery disease (CAD) severity and prognosis. MethodsForty Caucasian subjects, mean age 63.5 ± 7.6, with significant coronary artery lesions (≥50%) were included. Within two months of coronary angiography, TM and RE CPET were performed on two visits 2–4 days apart and subsequently followed up to 32 ± 10 months. ResultsMean left ventricular ejection fraction was 56.7 ± 9.6%. TM CPET exhibited a higher occurrence of ST segment depression ≥ 1 mm (71.05% vs 28.95%, p = 0.04). Subjects with 1–2 stenotic coronary arteries (SCA) demonstrated a better CPET response compared to those with 3-SCA. ROC analysis revealed a high predictive value for the ventilation/carbon dioxide production (VE/VCO2) slope obtained on TM (area 0.84, p = 0.003, Sn 88.9%, Sp 72%) in distinguishing between 1 and 2-SCA and 3-SCA. Among all CPET parameters, work efficiency (∆VO2/∆WR) during RE predicted cumulative cardiac events (p < 0.01). ConclusionsCPET parameters hold predictive value for CAD severity and prognosis. CPET on a TM appears to be more reliable in the quantification of CAD compared to RE.

Impact of Parental History of Hypertension on Heart Rate by Treadmill

The heart rate response to exercise is another determinant of the healthy cardiovascular system. Increased heart rate has been shown to be predictive of mortality and morbidity. A total of 100 subjects with parental history of hypertension were divided into two groups during pre exercise and post exercise period by tread mill. There was a significant decrease in heart rate after training. Heart rate variation has been shown to be predictive of mortality and morbidity in subjects with parental history of hypertension.

High Sensitivity C-Reactive Protein and Tread Mill Test Responses in Patients with Type 2 Diabetes Mellitus

High Sensitivity C-Reactive Protein and Tread Mill Test Responses in Patients with Type 2 Diabetes Mellitus

Systematic differences of gluteal muscle activation during overground and treadmill walking in healthy older adults

Guteal muscle activation during walkway and treadmill walking was compared by means of Surface EMG (SEMG). Healthy older adults (50–75 years, n = 54; 29 females, 25 males) walked on a walkway (WW) at their self-selected slow, normal, and fast walking speeds and on a treadmill (TM) at 2, 3, 4, 5, and 6 km/h. Subject-individual, best-matched speed pairs were constituted and named SLOW, NORMAL, and FAST. Hip muscle activation was measured on both sides at mid-distance between the greater trochanter and the iliac crest by applying eight equally-spaced bipolar SEMG channels from ventral to dorsal (P1–P8). Grand averaged amplitude curves and mean amplitudes over the complete stride were analyzed to compare WW and TM walking. TM walking evoked significantly elevated mean amplitude levels, particularly at the ventral positions P1 to P4, which were disproportionately increased at SLOW. In grand averaged curves, corresponding significant amplitude differences between WW and TM were observed during load acceptance (SLOW; NORMAL), mid-stance (all speeds), and late swing phase (SLOW), with the number of significant differences decreasing for all electrode positions from SLOW to FAST. Compared to WW walking, TM walking may thus require systematically elevated effort of gluteal muscles, in particular at slow walking speed.

Abstract 17026: Effects of Supervised Exercise Therapy on Free-Living Physical Activity Among Patients With Symptomatic Peripheral Artery Disease

Introduction: Evidence supporting the effects of supervised exercise therapy (SET) on alleviating symptoms and improving walking ability for patients with symptomatic peripheral artery disease (PAD) is robust and well recognized. However, little is known about the impact of SET on free-living physical activity (PA). The aim of this study was to examine the relationship between participation in SET and changes in free-living PA among individuals in the the EX ercise Training to Reduce Claudication: Arm ER gometry versus T readmill Walking ( EXERT ) trial. Methods: In this randomized, controlled trial, 104 participants (mean age 68±9; 29% female) were allocated to receive treadmill (TM) exercise (n=41), upper body ergometry (UBE) exercise (n=42), or usual-care (UC) (n=21) for 12 weeks. Exercise participants attended SET three times per week; UC participants met with study staff weekly. PA was measured over 7 days via waist-worn ActiGraph accelerometers at baseline, 6, and 12 weeks. Steps per day was the primary outcome. Secondary outcomes were proportion of time in light and moderate to vigorous physical activity (MVPA), and sedentary time. PA was controlled for in TM participants by using SET logs. Results were analyzed using descriptive statistics, two-sample t-tests, and analysis of variance. Results: Regardless of randomization, average daily steps were low at baseline and 6 weeks (4,013 steps, p =.72; and 3,911 steps, p =.84, respectively), and slightly higher at 12 weeks (4,307 steps; p =.93). Although not statistically significant but perhaps clinically relevant, UBE participants exhibited greater increases in MVPA over 12 weeks (0.9% to 1.3%; F =.48, p =.62) compared to TM (1.2% to 1.3%; F =.35, p =.71) and UC (1.3% to 1.5%, F =.03, p =.97); similarly all participants exhibited reductions in sedentary time and increases in free-living PA between baseline and 12 weeks. Conclusions: These data suggest individuals with PAD attending SET replace sedentary time with light or moderate intensity PA regardless of exercise modality. Despite study participants meeting the recommended daily steps for adults with chronic conditions (3,500-5,500 steps), it is suspected that they did not reach the daily goal of 30 minutes of enhanced PA to reduce health risks. Future research should incorporate activity tracking devices that can provide feedback on PA as an approach to meet daily PA goals. Activity tracking devices used in conjunction with SET may further improve walking distance, symptom management, and quality of life among patients with symptomatic PAD.

Metabolic Responses to a Battling Rope Protocol Performed in the Seated or Stance Positions

PURPOSE:To compare the levels of oxygen consumption (VO2) and heart rate (HR) responses elicited by a treadmill (TM) or bicycle (BK) VO2 max test with a standing or sitting battling rope protocol (BRP) (TM vs. standing BRP) (BK vs. seated BRP). To examine the associations between the peak HR and VO2 responses elicited from the two BRP with their respective VO2 max tests (TM vs. standing BRP) (BK vs. seated BRP). METHODS: Forty healthy subjects, 24 females and 16 males, mean age 24.83 years, performed either a ramped VO2 max TM or BK test (respiratory exchange ratio > 1.0). At least 3 days later, the subjects who performed the ramped TM test did the standing BRP, and the subjects who performed the ramped BK test did the sitting BRP. Each BRP (standing and sitting) consisted of 15 seconds of double arm swings, followed by 45 seconds of rest for 10 rounds. The highest recorded VO2 and HR values (VO2 peak and HR peak, respectively) were recorded after each round. RESULTS: Metabolic responses were significantly lower for the BRP in both sitting (VO2 peak and HR peak: p < .001) and standing (VO2 peak and HR peak: p < .001) as compared to the HR max and VO2 max values derived from the BK and TM tests. The BRP produced a VO2 peak that was 71.87% (sitting) and 68.37% (standing) of the subjects’ VO2 max assessed via the BK and TM protocol, respectively. Moderate correlations were found between the VO2 during the seated (r = .61; p =.003) and standing (r=.43; p=.03) BRP and the BK and TM VO2 max tests, respectively. The HR peak elicited by the BRP done in sitting (r = .52; p = .009) and standing (r = .67; p = .001) had a moderate correlation with the HR max derived from the BK and TM tests. CONCLUSIONS: Both the seated and standing BRPs demonstrated the capacity to produce acute metabolic responses that may enhance aerobic capacity. Battling ropes may be a low cost, accessible option to improve cardiovascular endurance for individuals who cannot stand or move their lower extremities in a rhythmic manner to conduct aerobic exercise.

Cardiometabolic Prediction Equations Overestimate Cardiorespiratory Fitness for Treadmill and Cycle Ergometry in Multiple Sclerosis Patients

Multiple sclerosis (MS) patients exhibit a decreased peak oxygen uptake (VO2peak) compared to age-matched peers, and therefore have the potential for increased relative gains in VO2peak in response to chronic exercise training. Individualized exercise prescriptions and monitoring improvement both rely on accurate assessment of VO2peak; however, expired gas analysis is not always available. Therefore, prediction equations have been established to estimate VO2peak for both treadmill (TM) and cycle ergometry (CE) tests based on work rates. Whether or not these equations are appropriate for MS patients has yet to be investigated. PURPOSE: To compare VO2peak obtained via TM and CE maximal exercise tests to previously established cardiometabolic prediction equations. METHODS: MS patients (44 ± 11 yrs, 28.1 ± 8.0 kg/m2, 11 ± 10 yrs since dx) performed a maximal graded exercise test on both a TM and CE. Twenty-five subjects completed the TM test, and 26 completed the CE test. TM tests consisted of 2 min stages with a constant, self-selected pace, with a 2% increase in grade per stage. CE tests increased by 15 Watts/min. VO2peak was compared to previously established mode-specific cardiometabolic prediction equations using paired samples t-tests and further examined with Bland-Altman plots. RESULTS: Predicted VO2peak was higher than measured values for both TM and CE (p<0.05). The TM had a mean bias, upper limit of agreement (LOA), and lower LOA of -2.35, 6.63, and -11.32 mL/kg/min, respectively. The CE had a mean bias, upper LOA, and lower LOA of -2.20, 3.31, and -7.72 mL/kg/min, respectively. CONCLUSION: Cardiometabolic prediction equations resulted in higher VO2peak estimates for both TM and CE in MS patients. The wide limits of agreement (Bland-Altman plots) suggest the accuracy in predicting individual VO2peak values is compromised among individuals with MS.Table: No title available.

A Prospective Study of Tread Mill Test in Postmenopausal Women

A Prospective Study of Tread Mill Test in Postmenopausal Women

Unmatched speed perceptions between overground and treadmill manual wheelchair propulsion in long-term manual wheelchair users

BackgroundManual wheelchair (MWC) propulsion is increasingly assessed on a motorized treadmill (TM), which is often considered more ecologically valid than stationary rollers. However, no clear consensus on the similarities between overground (OG) and TM propulsion has yet been reached. Furthermore, no study has investigated the participants’ perceptions of propelling a MWC on a TM compared to OG. Research questionThe present study aims to assess the perception of speed when propelling on a TM vs OG, and to relate this perception to measured spatiotemporal variables, kinetics and work. MethodsIn this repeated-measures study, the propulsion’s spatiotemporal variables, kinetics, and work of nineteen experienced wheelchair users with a spinal cord injury were compared between three conditions: 1) OG at a self-selected speed, 2) on a TM at a self-selected speed perceived as being similar to the OG speed (TMperceived), and 3) on a TM at the same speed as OG (TMmatched). Each variable was compared between conditions using an analysis of variance for repeated measures. ResultsAll participants selected a lower speed for TMperceived than OG, with a difference of −0.6 m/s (−44%). This adaptation may be due to a combination of two factors: 1) the absence of speed information, and 2) the feeling of urgency to grab the wheels during the recovery phase. The power output, work per cycle, and work per minute were also much lower on TMperceived than OG. However, in contrast to other work on MWC propulsion on a TM, the kinetic variables assessed were all similar between the OG and TMmatched conditions. SignificanceTraining on a TM should be performed at a speed that matches the OG speed and not at a self-selected speed on the TM, which would reduce the power output and work and therefore reduce the efficiency of the training.

Unique Sensory and Motor Behavior in Thy1-GFP-M Mice before and after Spinal Cord Injury.

Sensorimotor recovery after spinal cord injury (SCI) is of utmost importance to injured individuals and will rely on improved understanding of SCI pathology and recovery. Novel transgenic mouse lines facilitate discovery, but must be understood to be effective. The purpose of this study was to characterize the sensory and motor behavior of a common transgenic mouse line (Thy1-GFP-M) before and after SCI. Thy1-GFP-M positive (TG+) mice and their transgene negative littermates (TG-) were acquired from two sources (in-house colony, n = 32, Jackson Laboratories, n = 4). C57BL/6J wild-type (WT) mice (Jackson Laboratories, n = 10) were strain controls. Moderate-severe T9 contusion (SCI) or transection (TX) occurred in TG+ (SCI, n = 25, TX, n = 5), TG- (SCI, n = 5), and WT (SCI, n = 10) mice. To determine responsiveness to rehabilitation, a cohort of TG+ mice with SCI (n = 4) had flat treadmill (TM) training 42-49 days post-injury (dpi). To characterize recovery, we performed Basso Mouse Scale, Grid Walk, von Frey Hair, and Plantar Heat Testing before and out to day 42 post-SCI. Open field locomotion was significantly better in the Thy1 SCI groups (TG+ and TG-) compared with WT by 7 dpi (p < 0.01) and was maintained through 42 dpi (p < 0.01). These unexpected locomotor gains were not apparent during grid walking, indicating severe impairment of precise motor control. Thy1 derived mice were hypersensitive to mechanical stimuli at baseline (p < 0.05). After SCI, mechanical hyposensitivity emerged in Thy1 derived groups (p < 0.001), while thermal hyperalgesia occurred in all groups (p < 0.001). Importantly, consistent findings across TG+ and TG- groups suggest that the effects are mediated by the genetic background rather than transgene manipulation itself. Surprisingly, TM training restored mechanical and thermal sensation to baseline levels in TG+ mice with SCI. This behavioral profile and responsiveness to chronic training will be important to consider when choosing models to study the mechanisms underlying sensorimotor recovery after SCI.

Respiratory exchange ratio in aerobic exercise on treadmill versus cycle ergometer at similar perceived exertion

Background: Treadmill (TM) and cycle ergometer (CE) are the most commonly used indoor machines for aerobic exercise (AE). Previous studies have indicated that TM causes higher fat oxidation than CE AE; however, data from the Indian subcontinent are lacking regarding the same. Accumulation of visceral fat leads to various cardiovascular and metabolic disorders, and hence, AE modality that causes higher fat oxidation could prove more beneficial in improving health-related quality of life. Aims and Objectives: The aim of this study is to compare cardiovascular response and respiratory exchange ratio (RER) in TM and CE AE by moderately active males at similar ratings of perceived exertion (RPE). Materials and Methods: In the present experimental study, sixteen males with normal body mass index were involved to perform 30 min of continuous moderate intensity AE on TM and CE at RPE of 13. Systolic blood pressure (SBP) and diastolic blood pressure (DBP), heart rate (HR), and pulse pressure (PP) were analyzed just before and after the exercise trial. RER was estimated during the last 2 min of exercise. Paired t-test was applied to compare the means, and P < 0.05 was considered statistically significant. Results: HR after TM (136 ± 10) tended (P = 0.063) to be higher than CE (132 ± 9), while changes in SBP, DBP, and PP were non-significant. RER was non-significantly (P = 0.148) higher in CE (0.89 ± 0.05) than TM (0.91 ± 0.06). Oxygen consumption was significantly (P = 0.049) higher in TM (1.11 ± 0.17 L/min) than CE (1.03 ± 0.16 L/min). Conclusion: TM caused significantly higher energy consumption with non-significantly higher HR and fat oxidation than CE AE at RPE of 13.

Metabolic and Mechanical Effects of Laddermill Graded Exercise Testing.

Allerton, TD, Earnest, CP, and Johannsen, NM. Metabolic and mechanical effects of laddermill graded exercise testing. J Strength Cond Res 32(1): 195-200, 2018-The purpose of this study was to compare the metabolic responses and mechanical impact forces during a maximal graded exercise test (GXT) on a laddermill (LM) vs. a standard treadmill (TM). Twenty college-aged men (n = 10) and women completed a GXT on the TM and LM in random order. During the GXT, expired gases (V[Combining Dot Above]O2 and V[Combining Dot Above]CO2), heart rate, accelerometer data, blood lactate (BLa), and rating of perceived exertion (RPE) were collected in the last minute of each stage. Data were analyzed by paired t-tests and presented herein as mean ± SD. Treadmill exercise resulted in a higher V[Combining Dot Above]O2peak than LM exercise (45.6 ± 7.5 vs. 41.2 ± 5.6 ml·kg·min, p < 0.001). Blood lactate threshold was similar (p = 0.2) between LM (62 ± 17% V[Combining Dot Above]O2peak) and TM (68 ± 1% V[Combining Dot Above]O2peak). The average activity level experienced during LM (0.14 ± 0.04 vector magnitude unit [VMU]) exercise was lower (p < 0.0001) vs. TM (0.67 ± 0.01 VMU). Additionally, impact forces were reduced (p < 0.005) from the vertical plane during LM (-0.46 ± 0.12g) compared with TM (-0.81 ± 0.06g) exercise. Our results suggest that the nature of LM exercise does not elicit the same V[Combining Dot Above]O2peak response observed during TM exercise. However, impact forces were reduced and energy expenditure remained higher during LM testing, whereas RPE was similar between modalities. LM exercise may provide an alternative to individuals seeking to incur a negative energy balance, but to whom higher impact forces are detrimental.

Short-term effects of treadmill exercise on metabolic, physiological and hemodynamic functions of apparently healthy individuals.

Background: According to the World Health Organization (WHO), 60 to 85% of the population worldwide does not engage in enough activity; making physical inactivity the fourth leading risk factor for global mortality.Aims and Objectives: This study evaluated the effect of treadmill exercise on liver enzymes, lipid profile, glucose, albumin, blood pressure and pulse rate of apparently healthy students of Nigerian Law School, Enugu Campus, Enugu State Nigeria.Materials and Methods: Sixty (60) students (30 males and 30 females) within the age bracket of 21-35 years were recruited for this study. The anthropometric parameters: height (m) and weight (kg) were taken and used in the calculation of body mass index (BMI). Blood samples were collected from the subjects for the determination of liver enzymes, lipid profile, glucose and albumin levelsbefore and immediately after exercise. Anthropometric parameters, blood pressure and pulse rate were also measured before and immediately after exercise. The blood samples collected were analyzed in the laboratory for albumin, glucose, lipid profile (triglyceride, total cholesterol, high density lipoprotein (HDL) and low density lipoprotein (LDL)), liver enzyme (aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphate (ALP)) using standard methods as described in materials and methods.Results: There were significant difference (p&lt;0.05) between the mean pulse rate and blood pressure before and after treadmill exercise. There were also significant difference (p&lt;0.05) between the mean glucose, AST, ALT, ALP, total cholesterol and albumin before and after exercise.Conclusion: Findings from this study revealed that tread mill exercise has a short term effect of the metabolic, physiological and hemodynamic functions of the exercising individuals.Asian Journal of Medical Sciences Vol.9(1) 2018 27-31