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1.
Int J Exerc Sci ; 11(7): 503-515, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29541338

RESUMO

Wearable physical activity trackers are a popular and useful method to collect biometric information at rest and during exercise. The purpose of this systematic review was to summarize recent findings of wearable devices for biometric information related to steps, heart rate, and caloric expenditure for several devices that hold a large portion of the market share. Searches were conducted in both PubMed and SPORTdiscus. Filters included: humans, within the last 5 years, English, full-text, and adult 19+ years. Manuscripts were retained if they included an exercise component of 5-min or greater and had 20 or more participants. A total of 10 articles were retained for this review. Overall, wearable devices tend to underestimate energy expenditure compared to criterion laboratory measures, however at higher intensities of activity energy expenditure is underestimated. All wrist and forearm devices had a tendency to underestimate heart rate, and this error was generally greater at higher exercise intensities and those that included greater arm movement. Heart rate measurement was also typically better at rest and while exercising on a cycle ergometer compared to exercise on a treadmill or elliptical machine. Step count was underestimated at slower walking speeds and in free-living conditions, but improved accuracy at faster speeds. The majority of the studies reviewed in the present manuscript employed different methods to assess validity and reliability of wearable technology, making it difficult to compare devices. Standardized protocols would provide guidance for researchers to evaluate research-grade devices as well as commercial devices used by the lay public.

2.
Int J Exerc Sci ; 11(7): 526-532, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29541340

RESUMO

Since its debut in July 2016, Pokémon GO has been a wildly popular mobile gaming app. In contrast to many previous apps, Pokémon GO requires the user to be physically active. However, the extent to which Pokémon GO contributes to physical activity is unknown. Therefore, the purpose of this study was to investigate the physical activity profile of playing Pokémon GO for 60 minutes in recreationally active college students. College students (n=27, n=19 female) were fitted with an accelerometer, pedometer, and heart rate monitor to assess the activity demands during a 60-min bout of Pokémon GO. Troiano accelerometer cut points were utilized to estimate time spent in sedentary, light, moderate, and vigorous-intensity physical activity. Of the 60-min allotted playtime, accelerometry indicated 82% was achieved via moderate-to vigorous-intensity physical activity. Pedometer counts indicated approximately 6000-steps/100-steps/min, indicative of moderate-intensity physical activity. Heart rates were approximately 50% of age-predicted maximum, also indicative of moderate-intensity physical activity. The results of this study provide evidence that playing one hour of Pokémon GO can be an effective means of accumulating recommended levels of daily/weekly physical activity.

3.
Int J Exerc Sci ; 9(2): 223-229, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27182423

RESUMO

The purpose of this study was to compare the differences in metabolic and energy cost (MEC) of college students while seated, standing, and during a sitting/stepping protocol. Participants were assessed via indirect calorimetry for 20 min in each of the following conditions: 1) seated in a standard office chair, 2) standing in place, and 3) a sitting/stepping protocol in which participants performed 1 min of stepping in place at 90 bpm, sat for 9 min, then repeated the stepping and sitting sequence once more. Participants completed each of the 3 trials in the aforementioned order, preceded with a 3 min acclimation period in each condition. A significant difference in MEC was observed between the 3 conditions, p < 0.001. Pairwise comparisons indicated that the sitting/stepping protocol resulted in significantly greater MEC than the seated and standing conditions (p < 0.001). Additionally, the standing protocol resulted in significantly greater MEC than the seated protocol (p < 0.001). The significant differences and large effect sizes between conditions indicate that interspersing sedentary bouts with brief activity can substantially increase MEC. Broader application of these findings may provide health promotion professionals with novel strategies to reduce sedentary behavior and improve health.

4.
Wilderness Environ Med ; 26(2): 216-20, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25771026

RESUMO

OBJECTIVE: The purpose of this study was to compare the cardiovascular (CV) demands of 2 deer retrieval methods. METHODS: Twelve male participants (weight 86±24 kg, age 21±1 years) performed a maximum treadmill test on day 1 to determine baseline fitness levels. On day 2, all participants first towed, then dragged a 45-kg simulated deer carcass for 457 m at a self-selected pace. The tow condition utilized a shoulder harness system with a 2-m strap connecting the harness to the carcass, allowing the participant to walk upright as he towed the load. The dragging condition required the participants to flex their trunk, grasp the legs of the deer with both hands, and drag the carcass the length of the course. Heart rate and oxygen consumption (VO2) from each trial were measured by indirect calorimetry. RESULTS: The CV responses of towing were significantly less compared with those of dragging for VO2 peak (P=.001), peak heart rate (P=.003), average heart rate (P=.028), and rating of perceived exertion (P<.001). No significant differences were observed for average VO2 (P=.91) or time to completion (P=.27). CONCLUSIONS: The results of this study suggest towing a deer with a shoulder harness results in significant reductions in CV demand and lower perceived exertion compared with traditional deer dragging techniques. Deer hunters who are deconditioned or have CV risk factors are strongly encouraged to consider deer retrieval methods utilizing a shoulder harness and tow rope to mitigate the increased demands commonly found with traditional retrieval methods.


Assuntos
Cervos , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Animais , Humanos , Masculino , Adulto Jovem
5.
Int J Exerc Sci ; 8(1): 4-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27182410

RESUMO

The Astrand-Rhyming cycle ergometer test (ARCET) is a commonly administered submaximal test for estimating aerobic capacity. Whereas typically utilized in clinical populations, the validity of the ARCET to predict VO2max in a non-clinical population, especially female, is less clear. Therefore, the purpose of this study was to determine the accuracy of the ARCET in a sample of healthy and physically active college students. Subjects (13 females, 10 males) performed a maximal cycle ergometer test to volitional exhaustion to determine VO2max. At least 48 hours later, subjects performed the ARCET protocol. Predicted VO2max was calculated following the ARCET format using the age corrected factor. There was no significant difference (p=.045) between actual (41.0±7.97 ml/kg/min) and predicted VO2max (40.3±7.58 ml/kg/min). When split for gender there was a significant difference between actual and predicted VO2 for males, (45.1±7.74 vs. 42.7±8.26 ml/kg/min, p=0.029) but no significant difference observed for females, (37.9±6.9 vs. 38.5±6.77 ml/kg/min, p=0.675). The correlation between actual and predicted VO2 was r=0.84, p<0.001 with an SEE= 4.3 ml/kg/min. When split for gender, the correlation for males was r=0.94, p<0.001, SEE=2.72 ml/kg/min; for females, r=0.74, p=0.004, SEE=4.67 ml/kg/min. The results of this study indicate that the ARCET accurately estimated VO2max in a healthy college population of both male and female subjects. Implications of this study suggest the ARCET can be used to assess aerobic capacity in both fitness and clinical settings where measurement via open-circuit spirometry is either unavailable or impractical.

6.
J Strength Cond Res ; 29(4): 889-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23897017

RESUMO

Rope training, consisting of vigorously undulating a rope with the upper body, has become a popular cardiovascular training choice in fitness centers and athletic performance enhancement facilities. Despite widespread use and growing popularity, little is known about the metabolic demands of rope training. Therefore, the purpose of this study was to quantify the cardiovascular and metabolic cost from an acute 10-minute bout of rope training. Eleven physically active participants used a 15.2-m rope anchored by a post, resulting in the participant holding 7.6 m of rope in each hand. The 10-minute protocol consisted of 15 seconds of vertical double-arm waves followed by 45 seconds of rest for 10 total repetitions. The metabolic cost was estimated from heart rate, lactate, resting O2 uptake, exercise O2 uptake, and excess postexercise O2 consumption measurements. The average heart rate for the workout was 163 ± 11 b·min with peak (Equation is included in full-text article.) of 35.4 ± 5.4 mL·kg(-1)·min(-1), and peak METs were 10.1 ± 1.6. Total energy expenditure was 467.3 ± 161.0 kJ. When expressed per unit of time, EE was 41.3 ± 14.1 kJ·min(-1). The results of this study suggest an acute 10-minute bout of rope training in a vigorous-intensity workout, resulting in high heart rates and energy expenditure, which meet previously established thresholds known to increase cardiorespiratory fitness.


Assuntos
Metabolismo Energético/fisiologia , Consumo de Oxigênio/fisiologia , Condicionamento Físico Humano/fisiologia , Adulto , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Condicionamento Físico Humano/métodos , Descanso/fisiologia , Adulto Jovem
7.
Int J Exerc Sci ; 7(3): 212-219, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27182405

RESUMO

Post-activation potentiation (PAP) is a phenomenon in which the power output of a muscle is immediately enhanced after heavy resistance exercise. Whereas the majority of PAP research has examined males, minimal research exists as to how female athletes respond. Therefore, the purpose of this study was to investigate the acute PAP response of back squats on static squat jump (SSJ) performance among NCAA Division II female athletes. Female athletes (n=29) who were current roster members from basketball, softball, and volleyball, performed 3 SSJ prior to 3 repetitions of the back squat exercise at 90% 1RM. After a 5-min rest, athletes once again performed 3 SSJ for maximal height, with peak power calculated using the Sayers equation. There was a significant interaction effect observed between time and team, p=0.022; post-hoc tests indicated that the volleyball team had a significant decrease in power, p=0.008. The main effect for time was not significant, p=0.279, indicating for the group as a whole, there was no evidence of a PAP response. The main effect for team was also non-significant, p=0.173, indicating no difference in power outputs by team. Strength and conditioning coaches who work with female athletes should be aware that the successful implementation of PAP complexes within this population appears to be highly individualized. Therefore, the use of PAP complexes in female athletes should consider both the absolute and relative strength of each athlete in conjunction with the length of the rest period when attempting to optimize the PAP response.

8.
Int J Exerc Sci ; 7(4): 295-301, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27182407

RESUMO

The prevalence of overweight and obese in the U.S. has been thoroughly documented. With the advent of inactivity physiology research and the subsequent interest in sedentary behavior, the work environment has come under closer scrutiny as a potential opportunity to reverse inactivity. Therefore, the purpose of this study was to determine the sitting and physical activity (PA) habits among different classifications of university employees. University employees (n=625) completed an online survey based on the Occupational Sitting and Physical Activity Questionnaire (OSPAQ). Participants were instructed to describe time spent sitting, standing, walking, and in heavy physical labor during the last seven days, along with the number of breaks from sitting taken per hour. To establish habitual patterns of PA outside of work, employees recalled their participation in structured PA in the past seven days. Prior to data analysis, employees were categorized as Administration, Faculty, Staff, or Facilities Management. Statistically significant differences were found among employee classifications for min sit/d, p<.001; min stand/d, p<.001; min walk/d, p<.001; and min heavy labor/d, p<.001. No significant differences were found for breaks/h from sitting, p=.259 or participation in structured PA, p=. 33. With the exception of facilities management workers, university employees spent 75% of their workday seated. In conjunction with low levels of leisure time PA, university employees appear to be prime candidates for workplace interventions to reduce physical inactivity.

9.
Int J Exerc Sci ; 7(4): 311-317, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27182409

RESUMO

VO2 and heart rate (HR) are widely used when determining appropriate training intensities for clinical, healthy, and athletic populations. It has been shown that if the % reserve (%R) is used, rather than % of max, HR and VO2 can be used interchangeably to accurately prescribe exercise intensities. Thus, heart rate reserve (HRR) can be prescribed if VO2 reserve (VO2R) is known. Therefore, the purpose of this study was to compare VO2 R and HRR during moderate intensity exercise (50%R). Physically active college students performed a maximal treadmill test to exhaustion. During which VO2 and HR were monitored to determine max values. Upon completion of the maximal test, calculations were made to determine the % grade expected to yield approximately 50% of the subjects VO2R. Subjects then returned to complete the submaximal test (50%R) at least two days later. The %VO2R and %HRR were calculated and compared to the predicted value as well as to each other. Statistical analysis revealed that VO2 at 50%R was significantly greater than the actual VO2 achieved, p < .001. Conversely, the mean predicted HR at 50%R was significantly less than the actual HR achieved, p < .001. In conclusion, this study indicated that VO2 could be more accurately predicted than HR during moderate intensity exercise. The weak correlation between VO2R and HRR indicates that caution should be used when relying on a HR to determine VO2.

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