Exploring actual and perceived levels of physical activity intensity during virtual reality active games.

Background: Research suggests that engaging in active virtual reality (VR) video games can elicit light to moderate levels of physical activity (PA), making it a novel and fun mode of exercise. Further research is needed to understand the influence of VR on perceptions of exertion and enjoyment during PA. Objective: The objectives of this study are (1) to compare actual and perceived exertion within and between active VR games with varying levels of difficulty and (2) to determine how playing active VR games influences PA enjoyment during gameplay. Methods: A total of 18 participants completed four separate study sessions, during which they engaged in either a 15-min bout of traditional exercise (stationary cycling) or played one VR game. Heart rate (HR) and ratings of perceived exertion (RPE) using the Borg CR10 scale were assessed during VR gameplay and cycling. Enjoyment was measured after gameplay. VR games included playing Holopoint at level 2 and level 3 and Hot Squat. Repeated measures ANOVAs were used to examine (1) changes in HR and RPE across time within games and (2) differences in actual and perceived levels of intensity and enjoyment between games. Bivariate correlations examined the relationship between the degree of change in actual intensity and the degree of change in perceived intensity during each VR game and cycling. Results: The analyses revealed that RPE and HR significantly increased from baseline during each condition and generally increased across the 15-min of gameplay. Hot Squat and cycling elicited a significantly higher percentage of heart rate reserve (%HRR) than Holopoint at levels 2 and 3. Holopoint level 3 elicited a higher %HRR than Holopoint level 2. The participants reported greater average and max RPE during Hot Squat and cycling compared with Holopoint at levels 2 and 3. The correlations revealed a significant positive correlation between the degree of change in HR and RPE for cycling, but no significant correlations were observed for any of the VR conditions. The physical activity during Holopoint at both levels was rated as more enjoyable than Hot Squat and cycling. Conclusion: Our data support the notion that VR has the potential to alter individuals' perceptions of exertion during PA and, in particular, may reduce their awareness of increases in actual exertion.

Physical Activity to Prevent the Age-Related Decline of Endogenous Pain Modulation.

As humans age, the capacity of the central nervous system to endogenously modulate pain significantly deteriorates, thereby increasing the risk for the development of chronic pain. Older adults are the least physically active cohort of all age groups. We hypothesize that a sedentary lifestyle and decreased physical activity may contribute to the decline of endogenous pain modulation associated with aging.

Racial Differences in Head Pain and Other Pain-Related Outcomes After Mild Traumatic Brain Injury.

Recent research suggests that mild traumatic brain injury (TBI) may exert deleterious effects on endogenous pain modulatory function, potentially underlying the elevated risk for persistent headaches following injury. Accumulating research also shows race differences in clinical and experimental pain, with African Americans (AA) generally reporting more severe pain, worse pain modulation, and greater pain sensitivity compared with Caucasians. However, race differences in pain-related outcomes following mild TBI have rarely been studied. The purpose of this study was to explore race differences in endogenous pain modulation, pain sensitivity, headache pain, and psychological factors among AA and Caucasian individuals with mild TBI in the first month following injury compared with healthy controls and across time. Patients with mild TBI were recruited from local emergency department trauma centers. Sixty-three participants with mild TBI (AAs: n = 23, Caucasians: n = 40) enrolled in this study and completed study sessions at 1-2 weeks and 1-month post-injury. Forty-one mild-TBI-free control participants (AAs: n = 11, Caucasians: n = 30), matched on age and sex, completed one study session. Assessments included a Headache Survey, Pain Catastrophizing Scale, Center for Epidemiological Studies-Depression Scale (CES-D), and quantitative sensory testing (QST) to measure endogenous pain modulatory function. QST included conditioned pain modulation (CPM) to measure endogenous pain inhibitory function and temporal summation (TS) of pain and pressure pain thresholds (PPTs) of the head to measure pain sensitization and sensitivity. Two-way analysis of variance (ANOVA) was used to determine whether the outcome measures differed as a function of race, mild TBI, and time. Mediation analysis was used to explore potential mediators for the race differences in headache pain intensity. The results showed that AA participants with mild TBI reported significantly greater headache pain and pain catastrophizing and exhibited higher pain sensitivity and worse pain modulation on QST compared with Caucasian participants with mild TBI. These same race differences were not observed among the healthy TBI-free control sample. The mediation analyses showed complete mediation for the relation between race and headache pain intensity by pain catastrophizing at 1-2 weeks and 1-month post-injury. Overall, the results of this study suggest that AAs compared with Caucasians are characterized by psychological and pain modulatory profiles following mild TBI that could increase the risk for the development of intense and persistent headaches following injury.

Kinesiophobia Predicts Physical Function and Physical Activity Levels in Chronic Pain-Free Older Adults.

Advanced aging is associated with a general decline in physical function and physical activity. The current evidence suggests that pain-related fear of movement (i.e., kinesiophobia) is increased in the general older adult population and impacts physical activity levels in patients with chronic pain. However, whether kinesiophobia could impact physical activity and function in relatively healthy, chronic pain-free older adults remain unclear. Thus, the purpose of this study was to examine whether fear of movement due to pain predicted self-reported and objective levels of physical function and physical activity in healthy older adults without chronic pain. Fifty-two older adults were enrolled in this study. The participants completed the International Physical Activity Questionnaire (IPAQ) and wore an accelerometer on the hip for 7 days to measure physical activity. Measures of sedentary time, light physical activity, and moderate to vigorous physical activity were obtained from the accelerometer. Measures of physical function included the Physical Functioning subscale of the Short Form-36, Short Physical Performance Battery (SPPB), the 30-s Chair Stand test, and a maximal isometric hand-grip. The Tampa Scale of Kinesiophobia (TSK) was used to measure fear of movement or re-injury associated with pain. Potential covariates included self-reported activity-related pain and demographics. Hierarchical linear regressions were conducted to determine the relationship of kinesiophobia with levels of physical activity and physical function while controlling for activity-related pain and demographics. TSK scores did not predict self-reported physical activity on the IPAQ. However, TSK scores predicted self-reported physical function (Beta = -0.291, p = 0.015), 30-s Chair Stand test scores (Beta = -0.447, p = 0.001), measures from the SPPB (Gait speed time: Beta = 0.486, p < 0.001; Chair stand time: Beta = 0.423, p = 0.003), percentage of time spent in sedentary time (Beta = 0.420, p = 0.002) and light physical activity (Beta = -0.350, p = 0.008), and moderate to vigorous physical activity (Beta = -0.271, p = 0.044), even after controlling for significant covariates. These results suggest that greater pain-related fear of movement/re-injury is associated with lower levels of light and moderate to vigorous physical activity, greater sedentary behavior, and worse physical function in healthy, chronic pain-free older adults. These findings elucidate the potential negative impact of kinesiophobia in older adults who don't report chronic pain.

Physical activity behavior in the first month after mild traumatic brain injury is associated with physiological and psychological risk factors for chronic pain.

OBJECTIVE: The purpose of this study was to determine whether self-reported physical activity (PA) in the first month after mild traumatic brain injury (mTBI) predicts endogenous pain modulatory function and pain catastrophizing at 1 to 2 weeks and 1 month after injury in patients with mTBI. METHODS: Patients with mild traumatic brain injury completed study sessions at 1 to 2 weeks and 1 month after injury. Assessments included a headache survey, Pain Catastrophizing Scale, International Physical Activity Questionnaire-Short Form, and several quantitative sensory tests to measure endogenous pain modulatory function including conditioned pain modulation (CPM), temporal summation, and pressure pain thresholds of the head. Hierarchical linear regressions determined the relationship between the PA variables (predictors) and pain catastrophizing and pain modulation variables (dependent variables) cross-sectionally and longitudinally, while controlling for potential covariates. RESULTS: In separate hierarchical regression models, moderate PA, walking, and total PA at 1 to 2 weeks after injury predicted pain inhibition on the CPM test at 1 month, after controlling for significant covariates. In addition, a separate regression revealed that minutes sitting at 1 month predicted CPM at 1 month. Regarding predicting pain catastrophizing, the regression results showed that sitting at 1 to 2 weeks after injury significantly predicted pain catastrophizing at 1 month after injury. CONCLUSION: Greater self-reported PA, especially moderate PA, 1 to 2 weeks after injury longitudinally predicted greater pain inhibitory capacity on the CPM test at 1 month after injury in patients with mTBI. In addition, greater sedentary behavior was associated with worse pain inhibition on the CPM test and greater pain catastrophizing at 1 month after injury.

Effect of different Kinesio tape tensions on experimentally-induced thermal and muscle pain in healthy adults.

Athletes and rehabilitation specialists have used Kinesio tape (KT) to help alleviate pain symptoms. Currently, no clear mechanism exists as to why pain is relieved with the use of KT and whether the pain relieving effect is simply a placebo effect. Additionally, the most effective taping parameters (tension of tape) for pain reduction remain unknown. We used quantitative sensory testing to address these key gaps in the KT and pain literature. Using a repeated-measures laboratory design, we examined whether KT applied at different tensions reduces experimentally-induced pain compared to a no tape condition and KT with minimal tension. Heat pain thresholds (HPT's), pressure pain thresholds (PPT's), and pressure pain suprathreshold (PPS: 125% of PPT) tests were administered to the forearm prior to and during KT and no tape conditions. Tape was applied to the ventral forearm at 25% of max tension, 75% of max tension, and no tension (placebo). Repeated measures ANOVA's evaluated the pain outcomes between conditions and across time. KT had no significant effect on PPT's and HPT's (p's >0.05). The ANOVA on PPS revealed that KT applied at 25% of tension significantly reduced pain ratings from the pretest (M = 34.4, SE = 5.5) to post-test 1 (M = 30.3, SE = 4.7) and post-test 2 (M = 30.4, SE = 4.7). No other conditions significantly reduced suprathreshold pressure pain. However, pain ratings at posttest-1 during the no-tape condition (M = 36.4, SE = 5.3) were significantly greater than pain ratings during post-test 1 and post-test 2 of all three tape conditions. In conclusion, the current study revealed that KT applied at low tension is the optimal tension to reduce pressure-evoked muscle pain. Additionally, the results suggested that KT applied at low, high, or no tension may acutely prevent increased muscle sensitivity with repeated pressure stimulation.

Physical Activity Intensity, Perceived Exertion, and Enjoyment During Head-Mounted Display Virtual Reality Games.

Objectives: The purpose of this study was to determine the following: (1) the level of physical activity (PA) achieved during commercial active virtual reality (VR) games, and (2) which active VR games elicit higher enjoyment levels in young, healthy adults. Materials and Methods: Thirty-six participants completed four study sessions, each devoted to playing one of the following head-mounted display VR games for 15 minutes: Beat Saber (BS), Holopoint (HP), Hot Squat (HS), and Relax Walk VR. PA intensity measures included percentage of heart rate reserve (%HRR), ratings of perceived exertion (RPE), and accelerometry. Enjoyment was measured with the Physical Activity Enjoyment Scale (PACES) following each gaming session. Mixed-model analysis of variances were used to analyze the outcome measures. Results: The analyses showed that HS elicited significantly higher %HRR and RPE than BS, HP, and Relax Walk. HS was the only game to reach moderate intensity via %HRR. Accelerometer data showed that time in whole-body moderate-to-vigorous physical activity (MVPA) for HS was significantly greater than HP, which was greater than BS and Relax Walk. Also, males exhibited significantly more whole-body and upper limb MVPA compared with females during gameplay. BS and HP were rated significantly more enjoyable than HS and Relax Walk. Conclusions: Results from this study suggest that active VR games can elicit varying degrees of PA intensity levels in young healthy adults, with HS eliciting moderate intensity activity. The games rated highest in enjoyment required mostly arm movement and a perceived light exertion. ClinicalTrials: NCT04221139.

The role of deficient pain modulatory systems in the development of persistent post-traumatic headaches following mild traumatic brain injury: an exploratory longitudinal study.

BACKGROUND: Post-traumatic headache (PTH) is one of the most common and long-lasting symptoms following mild traumatic brain injury (TBI). However, the pathological mechanisms underlying the development of persistent PTH remain poorly understood. The primary purpose of this prospective pilot study was to evaluate whether early pain modulatory profiles (sensitization and endogenous pain inhibitory capacity) and psychological factors after mild TBI predict the development of persistent PTH in mild TBI patients. METHODS: Adult mild TBI patients recruited from Level I Emergency Department Trauma Centers completed study sessions at 1-2 weeks, 1-month, and 4-months post mild TBI. Participants completed the following outcome measures during each session: conditioned pain modulation to measure endogenous pain inhibitory capacity, temporal summation of pain and pressure pain thresholds of the head to measure sensitization of the head, Pain Catastrophizing Scale, Center for Epidemiological Studies - Depression Scale, and a standardized headache survey. Participants were classified into persistent PTH (PPTH) and no-PPTH groups based on the 4-month data. RESULTS: The results revealed that mild TBI patients developing persistent PTH exhibited significantly diminished pain inhibitory capacity, and greater depression and pain catastrophizing following injury compared to those who do not develop persistent PTH. Furthermore, logistic regression indicated that headache pain intensity at 1-2 weeks and pain inhibitory capacity on the conditioned pain modulation test at 1-2 weeks predicted persistent PTH classification at 4 months post injury. CONCLUSIONS: Overall, the results suggested that persistent PTH is characterized by dysfunctional alterations in endogenous pain modulatory function and psychological processes in the early stages following mild TBI, which likely exacerbate risk for the maintenance of PTH.

Active Gaming: It Is Not Just for Young People.

Whether active gaming is an appropriate method to facilitate moderate-intensity physical activity in older adults remains unclear. The purpose of this study was to evaluate the intensity of physical activity and enjoyment while playing three active video games in older adults compared with younger adults. Ten younger and 10 older adults played three active games on separate days. Participants played two 15-min periods per game: one period at a self-selected intensity and one period with structured instructions to maximize the movement. Physical activity intensity and enjoyment were measured during gameplay. The results indicated that older adults played games at significantly higher intensities (5.3 + 1.8 vs. 3.6 + 1.8 metabolic equivalents), spent less time in whole-body sedentary activity, and rated games more enjoyable compared with younger adults. With physical activity intensity being consistent with moderate-to-vigorous intensity for older adults during gameplay, the results suggest that active video games could be used as a cardiovascular tool for older adults.

Effect of Acute Bouts of Volume-Matched High-Intensity Resistance Training Protocols on Blood Glucose Levels.

Monroe, JC, Naugle, KM, and Naugle, KE. Effect of acute bouts of volume-matched high-intensity resistance training protocols on blood glucose levels. J Strength Cond Res 34(2): 445-450, 2020-Resistance exercise has the capability to alter glucose metabolism in healthy adults; however, to what extent single sessions of varying intensities of resistance exercise affect capillary glucose levels is not completely understood. The purpose of this study was to compare the effect of different resistance training intensities on capillary blood glucose levels in healthy adults. Thirteen resistance-trained men (age 24.4 ± 2.7 years) participated in an evaluation and 2 separate experimental resistance training sessions. The experimental sessions were a high-intensity resistance training session (HT) consisting of 7 sets of 3 repetitions at 90% of the participant's estimated 1 repetition maximum (e1RM), and a moderate-/high-intensity resistance training session (MT) consisting of 3 sets of 9 repetitions at 70% of the participant's e1RM. At least 7 days separated the completion of each session. Four glucose readings during each session were recorded using a capillary glucometer: G1 (baseline); G2 (pre-exercise); G3 (after exercise); and G4 (10 minutes after exercise). Results were analyzed using repeated-measures analysis of variances. Analysis revealed a significant decrease in blood glucose levels between G2 and G3, and G2 and G4 in both the HT and MT experimental sessions (p = 0.045). In addition, there was a significant difference in the magnitude of change in glucose levels from G2 to G3 between HT and MT (HT = -38.2 ± 5.3% SE, p = 0.042, MT = -22.2 ± 5.9% SE). Although both of the acute resistance exercise protocols decreased blood glucose levels in healthy men, a greater decrease in blood glucose levels from pre-exercise to post-exercise was observed in HT group compared with MT group.

The Decline of Endogenous Pain Modulation With Aging: A Meta-Analysis of Temporal Summation and Conditioned Pain Modulation.

The purpose of this article was to examine age-related changes in conditioned pain modulation (CPM) and temporal summation (TS) of pain using meta-analytic techniques. Five electronic databases were searched for studies, which compared measures of CPM and TS among healthy, chronic pain-free younger, middle-aged, and older adults. Eleven studies were included in the final review for TS and 11 studies were included in the review of CPM. The results suggested a moderate magnitude of difference in TS among younger and middle-aged/older adults, with the older cohorts exhibiting enhanced TS of pain. Considerable variability existed in the magnitude of the effect sizes, which was likely due to the different experimental methodologies used across studies (ie, interstimulus interval, stimulus type, and body location). In regards to CPM, the data revealed a large magnitude of difference between younger and older adults, with younger adults exhibiting more efficient pain inhibition. Differences in CPM between middle-aged and older adults were minimal. The magnitude of pain inhibition during CPM in older adults may depend on the use of concurrent versus nonconcurrent protocols. In summary, the data provided strong quantitative evidence of a general age-related decline in endogenous pain modulatory function as measured by TS and CPM. PERSPECTIVE: This review compared CPM and TS of pain among younger, middle-aged, and older adults. These findings enhance our understanding of the decline in endogenous pain modulatory function associated with normal aging.

An Exploratory Study of Endogenous Pain Modulatory Function in Patients Following Mild Traumatic Brain Injury.

BACKGROUND: Recent animal research suggests that mild traumatic brain injury (mTBI) facilitates abnormal endogenous modulation of pain, potentially underlying the increased risk for persistent headaches following injury. However, no human studies have directly assessed the functioning of endogenous facilitory and inhibitory systems in the early stages after an mTBI. OBJECTIVE: The purpose of this exploratory study was to examine trigeminal sensitization and endogenous pain inhibitory capacity in mTBI patients in the acute stage of injury compared with matched controls. We also examined whether post-traumatic headache pain intensity within the mTBI sample was related to sensitization and pain inhibitory capacity. METHODS: Twenty-four mTBI patients recruited from emergency departments and 21 age-, race-, and sex-matched controls completed one experimental session. During this session, participants completed quantitative sensory tests measuring trigeminal sensitization (pressure pain thresholds and temporal summation of pain in the head) and endogenous pain inhibition (conditioned pain modulation). Participants also completed validated questionnaires measuring headache pain, depression, anxiety, and pain catastrophizing. RESULTS: The results revealed that the mTBI group exhibited significantly decreased pressure pain thresholds of the head and decreased pain inhibition on the conditioned pain modulation test compared with the control group. Furthermore, correlational analysis showed that the measures of trigeminal sensitization and depression were significantly associated with headache pain intensity within the mTBI group. CONCLUSIONS: In conclusion, mTBI patients may be at risk for maladaptive changes to the functioning of endogenous pain modulatory systems following head injury that could increase risk for post-traumatic headaches.

Improving Active Gaming's Energy Expenditure in Healthy Adults Using Structured Playing Instructions for the Nintendo Wii and Xbox Kinect.

Naugle, KE, Carey, C, Ohlman, T, Godza, M, Mikesky, A, and Naugle, KM. Improving active gaming's energy expenditure in healthy adults using structured playing instructions for the Nintendo Wii and Xbox Kinect. J Strength Cond Res 33(2): 549-558, 2019-Professionals work constantly to increase energy expenditure and improve cardiovascular outcomes. A newer form of physical activity used to improve cardiovascular outcomes and increase energy expenditure while also providing entertainment is active gaming. The purpose was to determine energy expenditure and enjoyment levels during participation in different games played with a directed set of instructions designed to enhance movement. Twenty-one adults completed 6 sessions (1 familiarization and 5 experimental) on separate days. During 4 of the experimental sessions, participants played 1 of 4 active games for two 15-minute periods. Two active games were from Xbox Kinect and 2 were from Nintendo Wii. During the first period, participants played at a self-selected level of activity. During the second period, participants were given specific instructions for play during both active and down times within games. Participants wore a portable gas analyzer to measure energy expenditure. Resting energy expenditure was measured during session 6. Outcome measures were analyzed with 4 Game × 2 Period repeated-measures analyses of variance. Energy expenditure, measured in metabolic equivalents (METS), was greatest while playing Kinect Fighter Within. METS, enjoyment levels, and percentage of time spent in whole-body activity were greater during the period with specific instructions compared to the self-selected levels of activity, regardless of active game. When played at a self-selected level of activity, energy expenditure during the active games was similar to that of light physical activity. However, energy expenditure improved during the second period of game play showing that specific instructions created energy expenditure of moderate intensity.

Physical Activity Levels Predict Exercise-induced Hypoalgesia in Older Adults.

Prior research indicates that older adults exhibit a deficient capacity to activate multiple pain inhibitory mechanisms, including pain inhibition after acute exercise termed exercise-induced hypoalgesia (EIH). The influence of physical activity levels and psychological processes on EIH in older adults remains unclear. PURPOSE: This study examined potential psychological and physical activity predictors of the magnitude of EIH after submaximal isometric exercise in healthy older adult men and women. METHODS: Fifty-two healthy older adults completed a test of EIH, the Pain Catastrophizing Scale, the Tampa Scale of Kinesiophobia, and wore an accelerometer on the hip for 1 wk to assess physical activity levels. For the test of EIH, participants complete a 3-min isometric handgrip at 25% of maximum voluntary contraction. Pressure pain thresholds (PPT) and a 30-s continuous heat pain test were completed before and immediately after the exercise. RESULTS: Mixed-model ANOVA revealed that older adults demonstrated significantly decreased PPT after isometric exercise (P = 0.030), and no changes on the heat pain trials from pretest to posttest (P > 0.05). A multiple regression revealed that accumulated moderate to vigorous physical activity (MVPA) per week significantly predicted the change in PPT after exercise (ß = 0.35, P = 0.012). Participants who averaged greater MVPA experienced a greater increase in PPT after exercise. No relationships were found with EIH and the psychological variables. CONCLUSIONS: Older adults did not exhibit EIH after submaximal isometric exercise. However, those who did more MVPA per week experienced a greater magnitude of pain inhibition after acute exercise.

Loss of Temporal Inhibition of Nociceptive Information Is Associated With Aging and Bodily Pain.

An age-related decline in endogenous pain inhibitory processes likely places older adults at an increased risk for chronic pain. Limited research indicates that older adults may be characterized by deficient offset analgesia, an inhibitory temporal sharpening mechanism that increases the detectability of minor decreases in noxious stimulus intensity. The primary purpose of the study was to examine age differences in offset analgesia in community-dwelling younger, middle-aged, and older adults. An additional aim of the study was to determine whether the magnitude of offset analgesia predicted self-reported bodily pain. Eighty-seven younger adults, 42 middle-aged adults, and 60 older adults completed 4 offset analgesia trials and 3 constant temperature trials in which a noxious heat stimulus was applied to the volar forearm for 40 seconds. The offset trials consisted of 3 continuous phases: an initial 10-second painful stimulus, either a 1.0°C or .4°C increase in temperature from the initial 10-second painful stimulus for 10 seconds, and either a 1.0°C or .4°C decrease back to the initial testing temperature for 20 seconds. During each trial, subjects rated pain intensity continuously using an electronic visual analog scale (0-100). All subjects also completed the Short-Form Health Survey-36 including the Bodily Pain subscale. The results indicated that older and middle-aged adults showed reduced offset analgesia compared with younger adults in the 1.0°C and .4°C offset trials. Furthermore, the magnitude of offset analgesia predicted self-reported bodily pain, with those exhibiting reduced offset analgesia reporting greater bodily pain. Dysfunction of this endogenous inhibitory system could increase the risk of developing chronic pain for middle-aged and older adults. PERSPECTIVE: Older and middle-aged adults showed reduced offset analgesia compared with younger adults. The significant association between reduced offset analgesia and pain in daily life supports the notion that pain modulatory deficits are associated with not just a chronic pain condition but with the experience of pain in general.

Active Gaming as a Form of Exercise to Induce Hypoalgesia.

OBJECTIVE: An acute bout of moderate-to-vigorous exercise temporarily reduces pain sensitivity in healthy adults. Recently, active gaming has been rising in popularity as a means of light-to-moderate exercise and may be particularly suitable for deconditioned individuals. Whether the physical activity elicited in active games can produce a hypoalgesic effect remains unknown. The purpose of this study was to determine whether active videogames can reduce pressure and heat pain sensitivity in healthy adults. We also evaluated the relationship between the physical activity elicited by the games and the magnitude of the hypoalgesic response. MATERIALS AND METHODS: Twenty-one healthy adults played four different active games on separate days, including Microsoft® Kinect Xbox® One's Fighter Within and Sports Rival's Tennis, and Nintendo® Wii™ Sports' Boxing and Tennis. Heat pain thresholds on the forearm and pressure pain thresholds (PPTs) on the trapezius and forearm were assessed immediately before and after a 15-minute active gaming or control session. Minutes spent in sedentary time and moderate-to-vigorous physical activity (MVPA) during active gaming were measured with an accelerometer. RESULTS: The analyses revealed that PPTs at the forearm and trapezius significantly increased from pretest to posttest following Kinect Fighter Within. PPTs at the trapezius also significantly increased from pretest to posttest following Wii Boxing. The magnitude of the hypoalgesic response was significantly correlated with MVPA and sedentary time during gameplay. CONCLUSION: These results suggest that an active gaming session played at a moderate intensity is capable of temporarily reducing pain sensitivity.

Physical activity behavior predicts endogenous pain modulation in older adults.

Older adults compared with younger adults are characterized by greater endogenous pain facilitation and a reduced capacity to endogenously inhibit pain, potentially placing them at a greater risk for chronic pain. Previous research suggests that higher levels of self-reported physical activity are associated with more effective pain inhibition and less pain facilitation on quantitative sensory tests in healthy adults. However, no studies have directly tested the relationship between physical activity behavior and pain modulatory function in older adults. This study examined whether objective measures of physical activity behavior cross-sectionally predicted pain inhibitory function on the conditioned pain modulation (CPM) test and pain facilitation on the temporal summation (TS) test in healthy older adults. Fifty-one older adults wore an accelerometer on the hip for 7 days and completed the CPM and TS tests. Measures of sedentary time, light physical activity (LPA), and moderate to vigorous physical activity (MVPA) were obtained from the accelerometer. Hierarchical linear regressions were conducted to determine the relationship of TS and CPM with levels of physical activity, while controlling for demographic, psychological, and test variables. The results indicated that sedentary time and LPA significantly predicted pain inhibitory function on the CPM test, with less sedentary time and greater LPA per day associated with greater pain inhibitory capacity. Additionally, MVPA predicted pain facilitation on the TS test, with greater MVPA associated with less TS of pain. These results suggest that different types of physical activity behavior may differentially impact pain inhibitory and facilitatory processes in older adults.

Increased spatial dimensions of repetitive heat and cold stimuli in older women.

Protocols of temporal summation (TS) of pain typically involve the delivery of brief repetitive noxious pulses of a constant intensity while measuring the perceived intensity of pain after each pulse. The size percept of noxious repetitive stimulation has been poorly characterized. Furthermore, no studies have investigated age differences in TS of cold pain. The current study examined TS of pain intensity and the perceived size of the painful area during repetitive noxious heat and cold pulses in healthy younger (n = 104) and older adults (n = 40). Trials of 10 brief repetitive noxious heat or cold pulses were delivered to the upper extremities. Participants rated the perceived size of the painful area or intensity of pain after each pulse. The magnitude of change for the size percept and intensity for pain were calculated for each trial. The results indicated that older adults experienced greater TS of the size percept of cold stimuli compared with younger adults. Additionally, older women experienced greater TS of the size percept of heat stimuli compared with older men and all younger participants. No overall age or sex differences were found in the TS of pain intensity for cold or heat trials. These results suggest dysfunctional modulation of the spatial percept of the painful stimuli by older adults, and in particular older women, during repetitive noxious thermal pulses.

Novel method for assessing age-related differences in the temporal summation of pain.

Temporal summation (TS) of pain protocols typically involve the delivery of brief repetitive noxious stimuli held at a constant intensity and measuring the consequent increase in the perceived intensity of pain sensations. To date, no studies have examined the effect of a TS protocol on the perceived spatial dimensions of the pain experience and its interaction with age. This study used a new TS protocol that examined changes in the perceived size of the painful area in 22 younger adults and 20 older adults. Four trials of ten brief heat pulses delivered at a constant intensity were administered on the volar forearm. Interpulse intervals (IPIs) were 2.5 seconds or 3.5 seconds. Subjects rated the peak pain intensity (trials 1 and 3) or the size of the painful area (trials 2 and 4) after each pulse on a 0-100 scale. The magnitude of summation was calculated for each trial. Three seconds and 6 seconds after delivering the last heat pulse, the subjects rated the intensity or the size of any remaining pain (aftersensations). The results indicated that older adults compared to younger adults exhibited significantly greater summation of size ratings for the 2.5-second and 3.5-second IPI trials and size of pain aftersensations at 3 seconds following the 2.5-second IPI TS trial. These results suggest that aging is associated with enhanced endogenous facilitation of the perceived size of pain. The potential clinical and mechanistic implications of enhanced TS of size of pain remain unknown and warrant further investigation.

Reduced Modulation of Pain in Older Adults After Isometric and Aerobic Exercise.

UNLABELLED: Laboratory-based studies show that acute aerobic and isometric exercise reduces sensitivity to painful stimuli in young healthy individuals, indicative of a hypoalgesic response. However, little is known regarding the effect of aging on exercise-induced hypoalgesia (EIH). The purpose of this study was to examine age differences in EIH after submaximal isometric exercise and moderate and vigorous aerobic exercise. Healthy older and younger adults completed 1 training session and 4 testing sessions consisting of a submaximal isometric handgrip exercise, vigorous or moderate intensity stationary cycling, or quiet rest (control). The following measures were taken before and after exercise/quiet rest: 1) pressure pain thresholds, 2) suprathreshold pressure pain ratings, 3) pain ratings during 30 seconds of prolonged noxious heat stimulation, and 4) temporal summation of heat pain. The results revealed age differences in EIH after isometric and aerobic exercise, with younger adults experiencing greater EIH compared with older adults. The age differences in EIH varied across pain induction techniques and exercise type. These results provide evidence for abnormal pain modulation after acute exercise in older adults. PERSPECTIVE: This article enhances our understanding of the influence of a single bout of exercise on pain sensitivity and perception in healthy older compared with younger adults. This knowledge could help clinicians optimize exercise as a method of pain management.