Examination of contraction-induced muscle pain as a behavioral correlate of physical activity in women with and without fibromyalgia

Abstract

Purpose: This study aimed to compare muscle pain intensity during a sustained isometric contraction in women with and without fibromyalgia (FM), and examine the association between muscle pain and self-reported levels of physical activity. Methods: Fourteen women with FM and 14 healthy women completed the study, where muscle pain ratings (MPRs) were obtained every 30?s during a 3?min isometric handgrip task at 25% maximal strength, and self-reported physical activity was quantified using the Baecke Physical Activity Questionnaire. Results: Women with FM were less physically active than healthy controls. During the isometric contraction, MPR progressively increased in both groups at a comparable rate, but women with FM generally reported a greater intensity of muscle pain than healthy controls. Among all women, average MPR scores were inversely associated with self-reported physical activity levels. Conclusions: Women with FM exhibit augmented muscle pain during isometric contractions and reduced physical activity than healthy controls. Furthermore, contraction-induced muscle pain is inversely associated with physical activity levels. These observations suggest that augmented muscle pain may serve as a behavioral correlate of reduced physical activity in women with FM.

• Implications for Rehabilitation

• Women with fibromyalgia experience a greater intensity of localized muscle pain in a contracting muscle compared to healthy women.

• The intensity of pain during muscle contraction is inversely associated with the amount of physical activity in women with and without fibromyalgia.

• Future studies should determine whether exercise adherence can be improved by considering the relationship between contraction-induced muscle pain and participation in routine physical activity.

     

Cardiorespiratory fitness, physical activity level, and chronic pain: are men more affected than women?

OBJECTIVE: To evaluate the cardiorespiratory endurance (CRE) and physical activity level of patients with chronic pain compared with healthy subjects. DESIGN AND SUBJECTS: Cross-sectional study, with a consecutive sample of 55 patients with chronic pain (20 men, 35 women). Comparison of CRE and physical activity indices obtained in patients with data available in the literature for age-matched healthy subjects. SETTING: A multidisciplinary pain center in a city of more than 1,000,000 inhabitants. OUTCOME MEASURES: A physical working capacity index (PWC65%/kg) and physical activity level scores and subscores obtained with two questionnaires (the Baecke and the Five-City Project questionnaires). RESULTS: The physiological gender difference in CRE indices that characterizes healthy subjects was not observed in patients with chronic pain. When compared with values previously obtained in controls, male patients presented with a very significant 34% reduction in PWC65%/kg. The 17% reduction found in women hardly reached significance level. The Baecke total physical activity score was significantly higher in female than in male patients, a finding not observed in healthy controls. There was no significant difference between male and female patients in the Five-City Project total physical activity score expressed in kilocalories per day per kilogram (i.e., normalized for body weight), although data from the literature show that healthy men present with a significantly higher level of physical activity compared with healthy women. CONCLUSIONS: Data on CRE and the physical activity level of patients with chronic pain obtained in this study show that chronic pain may have a greater impact on male than female patients. Sociocultural factors are probably at the origin of this phenomenon.     

Handgrip strength test as a complementary tool in the assessment of fibromyalgia severity in women

Aparicio VA, Ortega FB, Heredia JM, Carbonell-Baeza A, Sjöström M, Delgado-Fernandez M. Handgrip strength test as a complementary tool in the assessment of fibromyalgia severity in women.

Objectives

To determine the ability of handgrip strength test to discriminate between presence and absence of fibromyalgia (FM) and FM severity in women.

Design

A case-control study.

Setting

Granada, south Spain.

Participants

Women with FM (mean age ± SD, n=81; 50.0±7y) and healthy women (mean age ± SD, n=44; 47.7±6y).

Interventions

Not applicable.

Main Outcome Measures

Handgrip strength was measured in both hands (average score was used in the analyses) by a maximal isometric test using a hand dynamometer. Patients were classed as having moderate FM if the score in the Fibromyalgia Impact Questionnaire (FIQ) was less than 70 and as having severe FM if the FIQ was 70 or greater.

Results

Handgrip strength levels were lower in patients with FM than healthy women (19.3 vs 27.9kg; P<.001) and in women with severe FM (FIQ≥70) compared with those with moderate FM (FIQ<70) (16.9 vs 20.2kg; P=.02). Receiver operating characteristic curve analyses revealed that the handgrip strength threshold that best discriminated between the presence and absence of FM was 23.1kg (area under the curve [AUC]=.88; 95% confidence interval [CI], 0.82–0.94; P<.001), whereas the handgrip strength threshold that best discriminate between severe and moderate FM was 16.9kg (AUC=.67; 95% CI, 0.53–0.80; P<.05). Logistic regression analysis showed that handgrip strength 23.1kg or less was associated with 33.8 times higher odds (95% CI, 9.4–121.5) for having FM after adjustment for age. In the FM group, handgrip strength 16.9kg or less was associated with 5.3 times higher odds (95% CI, 1.9–14.5) for having severe FM.

Conclusions

Handgrip strength is reduced in women with FM as well as those with severe FM from their peers with moderate FM. Identification of women who fail to meet the suggested standards can be a helpful and informative tool for clinician.     

When It Hurts,a Positive Attitude May Help. The Moderating Effect of Positive Affect on the Relationship Between Walking,Depression, and Symptoms in Women with Fibromyalgia

Background: Increased exercise is a marker of health in fibromyalgia (FM). However, patients frequently avoid physical activity as a way of minimizing the pain they feel. This deprives them of opportunities to obtain positive reinforcement, increasing functional impact. Aims: This study examines the mediating role of depressive symptoms between walking (as physical exercise), functional impact, and pain, at different levels of positive affect (PA) among women with fibromyalgia. Design: Cross-sectional correlational study. Settings: Mutual aid associations for fibromyalgia in Spain. Participants: 231 women diagnosed with FM. Methods: Moderate mediation analyses were conducted using PROCESS. Results: First, a simple mediation model showed that depression mediated the effect of walking on functional impact, but not on pain. Additionally, the moderated mediated model showed that this effect was significant at medium and high levels of PA, but not when levels of PA were low. Conclusions: Provision of resources focused on positive affect seem to increase the positive effects of walking on functional impact through the reduction of depressive symptoms. Nurses can improve adherence of patients with FM to walking behavior through increasing positive affect.     

Factors promoting sustainable work in women with fibromyalgia

Abstract

Purpose: To examine and describe the factors promoting sustainable work in women with fibromyalgia (FM). Methods: A qualitative interview study. Twenty-seven gainfully employed women with FM participated in five focus group interviews. Their median age was 52 years, ranging from 33 to 62. The interviews were recorded, transcribed verbatim and analysed by qualitative latent content analysis. Results: Four categories were identified describing factors promoting sustainable work: the meaning of work and individual strategies were individual promoters while a favourable work environment and social support outside work were environmental promoters. The meaning of work included individual meaning and social meaning. The individual strategies included handling symptoms, the work day and long-term work life. A favourable work environment included the physical and psychosocial work environment. Social support outside work included societal and private social supports. Conclusions: Promoting factors for work were identified, involving individual and environmental factors. These working women with FM had developed advanced well-functioning strategies to enhance their work ability. The development of such strategies should be supported by health-care professionals as well as employers to promote sustainable work in women with FM.

• Implications for Rehabilitation

• Work disability is a common consequence of fibromyalgia (FM).

• Working women with FM appear to have developed advanced well-functioning individual strategies to enhance their work ability.

• The development of individual strategies should be supported by health-care professionals as well as employers to promote sustainable work and health in women with FM.

     

Genuine, suppressed and faked facial behavior during exacerbation of chronic low back pain.

Facial activity was examined as 60 female and 60 male chronic low back pain patients responded to a painful range of motion exercise during a scheduled physical examination. Subsequently, they were asked to fake the facial response to the movement inducing the most pain or to attempt to suppress evidence that they were experiencing pain when this same movement was again repeated. Facial behavior was measured using the Facial Action Coding System. Self-reports of pain also were provided. The genuine expression was consistent with that observed in previous research, but minor differences indicated that the facial display of pain reflects differences between sources of pain, social context in which pain is induced and individual differences among patients. Considerable voluntary control over the facial expression of pain was observed, although the faked expression was more an intensified caricature of the genuine expression, and an attempt to suppress the facial grimace of pain was not entirely successful as residual facial activity persisted. Self-reports were only moderately correlated with facial behavior.     

A comparison of physical functional performance and strength in women with fibromyalgia, age- and weight-matched controls, and older women who are healthy

BACKGROUND AND PURPOSE: The purpose of this study was to compare functionality and strength among women with fibromyalgia (FM), women without FM, and older women. SUBJECTS: Twenty-nine women with FM (age [X+/-SD]=46+/-7 years), 12 age- and weight-matched women without FM (age=44+/-8 years), and 38 older women who were healthy (age=71+/-7 years) participated. METHODS: The Continuous Scale-Physical Functional Performance Test (CS-PFP) was used to assess functionality. Isokinetic leg strength was measured at 60 degrees/s, and handgrip strength was measured using a handgrip dynamometer. RESULTS: The women without FM had significantly higher functionality scores compared with women with FM and older women. There were no differences in functionality between women with FM and older women. Strength measures for the leg were higher in women without FM compared with women with FM and older women, and both women with and without FM had higher grip strengths compared with older women. DISCUSSION AND CONCLUSION: This study demonstrated that women with FM and older women who are healthy have similar lower-body strength and functionality, potentially enhancing the risk for premature age-associated disability.     

Defective Endogenous Pain Modulation in Fibromyalgia: A Meta-Analysis of Temporal Summation and Conditioned Pain Modulation Paradigms

To study the characteristics of temporal summation (TS) and conditioned pain modulation (CPM) in fibromyalgia (FM) patients, we systematically searched Pubmed and EMBASE for studies using TS or CPM comparing FM patients with healthy controls. We computed Hedges' g, risk of bias, sensitivity analysis, and meta-regression tests with 10,000 Monte-Carlo permutations. Twenty-three studies (625 female and 23 male FM patients and 591 female and 81 male healthy controls) were included. The meta-analyses showed an effect size of .53 for TS (P?<?.001; 95% confidence interval = .23–.83), which is a 68% relative difference between patients and controls, and of .57 for CPM (P?<?.001; 95% confidence interval = ?.88 to ?.26), representing a 65% relative difference between the groups. The qualitative analyses revealed large heterogeneity between study protocols. Although studies were of low risk of bias, lack of blinding was substantial. Sensitivity analysis and meta-regression identified type and site of stimulation, age, lab, sample size, and medication control as important sources of between-study variability. We showed a significant alteration of pain modulation mechanisms in FM patients.

Pain Variability in Fibromyalgia Is Related to Activity and Rest: Role of Peripheral Tissue Impulse Input

Because fibromyalgia (FM) patients frequently report activity-dependent deep tissue pains, impulse input from painful body regions may be relevant for their musculoskeletal complaints. In addition, peripheral impulse input may induce and maintain thermal and mechanical hyperalgesia of FM patients. If so, activity and rest may alternately enhance and diminish intensity of FM pain. However, the effects of exercise on pain are ambiguous in studies of FM. Whereas exercise-only studies demonstrated increased pain and hyperalgesia during and after physical activity, some exercise studies that included rest periods resulted in decreased FM pain and increased function. To further clarify these effects, we examined the effects of alternating exercise with rest on clinical pain and thermal/mechanical hyperalgesia of 34 FM patients and 36 age-matched healthy controls (NC). Using an ergometer, all subjects performed arm exercise to exhaustion twice alternating with 15-minute rest periods. Although strenuous muscle activity was reported as painful by most FM subjects, overall clinical pain consistently decreased during the rest periods. Additionally, FM subjects' pain sensitivity to mechanical pressure decreased after each exercise and rest session. Conclusion: Alternating strenuous exercise with brief rest periods not only decreased overall clinical pain of FM subjects but also their mechanical hyperalgesia. No prolonged worsening of overall FM pain and hyperalgesia occurred despite vigorous muscle activity. Our findings contribute further evidence that FM pain and hyperalgesia are at least partially maintained by muscle impulse input, and that some types of exercises may be beneficial for FM.     

不同妊娠期正常孕妇及产科早期DIC患者PT、APTT、TT、FIB、D-D、FM变化的探讨

目的研究正常孕妇妊娠各期及产科早期弥漫性血管内凝血（DIC）患者凝血酶原时间（PT）、部分凝血活酶时间（APTT）、凝血酶时间（TT）、纤维蛋白（FIB）、D-二聚体（D-D）及纤维蛋白单体（FM）水平的变化。方法分别检测30例正常对照组妇女、90例正常妊娠妇女（妊娠早期30例、妊娠中期30例、妊娠晚期30例）及10例产科早期DIC患者的PT、APTT、TT、FIB、D-D及FM水平。结果正常孕妇组妊娠早期的PT及妊娠中、晚期的APTT、TT、FIB、FM与正常对照组比较,差异均有统计学意义（P〈0.001）;正常孕妇组妊娠各期D-D水平均高于正常对照组（P〈0.001）。产科早期DIC组与正常孕妇组妊娠各期及正常对照组比较,各项指标均有差异（P〈0.001）。正常孕妇组妊娠中、晚期PT、APTT较妊娠早期明显缩短（P〈0.001）,FM水平明显升高（P〈0.001）;TT、FIB、D-D水平在正常孕妇组妊娠各期中均有差异（P〈0.05、P〈0.001）。结论妊娠不同期,正常孕妇凝血机制会发生改变。一旦有早期DIC的发生FM水平会有较明显的升高,因此,FM指标的检测相对于D-D检测在确定早期DIC有着较明确的标识。对发现早期凝血异常有一定的帮助。     

Living with fibromyalgia: Sense of coherence,perception of well-being,and stress in daily life

Fibromyalgia (FM) is a chronic pain syndrome that has a considerable impact on the ill person's daily life. The purpose of this study was to describe levels of sense of coherence (SOC), perceptions of well-being, and stress in daily life in women with FM in comparison with healthy women, and to determine whether SOC is related to perceived levels of stress and well-being. Thirty women with FM were compared with 30 healthy women matched for Type A behavior. The results revealed a complex picture of the women with FM. On the one hand, they reported many symptoms but, on the other, they rated themselves as feeling quite well and experiencing an SOC in life, despite severe problems. The FM women with a stronger SOC perceived greater well-being than those with a weaker SOC. They felt more hopeful, more free, more valuable, and more like others. Results suggest that women with a weaker SOC may need extra support. More research is needed to investigate the experience of living with FM in order to discover what it is that makes life worthwhile despite high symptom levels. © 1997 John Wiley & Sons, Inc. Res Nurs Health 20: 495–503, 1997     

Confirmatory factor analysis of the Tampa Scale for Kinesiophobia: invariant two-factor model across low back pain patients and fibromyalgia patients

OBJECTIVES: (1) To investigate the factor structure of the Tampa Scale for Kinesiophobia (TSK) in a Dutch-speaking sample of chronic low back pain (CLBP) patients using confirmatory factor analysis, (2) to examine whether the internal structure of the TSK extends to another group of fibromyalgia (FM) patients, and (3) to investigate the stability of the factor structure in both patient groups using multi-sample analysis. PATIENTS AND METHODS: TSK-data from 8 studies collected in Dutch and Flemish chronic pain patients were pooled. For 188 CLBP patients and 89 FM patients, complete data were available. Confirmatory factor analyses were performed to assess 4 models of kinesiophobia, and to examine which factor model provided the best fit. Furthermore, a multi-sample analysis was performed to investigate the stability of the factor structure in both patient groups. RESULTS: For both CLBP and FM patients, the 2-factor model containing the factors "activity avoidance" and "pathologic somatic focus" was superior as compared with the 4-factor model containing the factors "harm," "fear of (re)injury." "importance of exercise," and "avoidance of activity". Moreover, the 2-factor model was found to be invariant across CLBP and FM patients, indicating that this model is robust in both pain samples. DISCUSSION: As the 2-factor structure provided the best fit of the data in both patient samples, we recommend to use this version of the TSK and its 2 subscales in both clinical practice and research. Based on the content of the items, the subscales were labeled "Harm" and "Fear-avoidance."     

A comparison of physical fitness in patients with bipolar disorder,schizophrenia and healthy controls

Purpose: To compare the physical fitness of inpatients with bipolar disorder, schizophrenia and healthy controls.

Method: Twenty-two inpatients with bipolar disorder, and 22 age-, gender- and body mass index-matched inpatients with schizophrenia and healthy controls were included. All participants performed the Eurofit test battery and the International Physical Activity Questionnaire. One way analyses of variance with post hoc Scheffe were applied to examine differences.

Results: Both patient groups were significantly more physically inactive and had a significantly impaired speed of limb movement, explosive muscle strength and abdominal muscular endurance compared to the healthy controls. No significant differences between the patient groups were found.

Conclusions: The results suggest that physical fitness and physical activity participation are similar among inpatients with bipolar disorder and schizophrenia but markedly lower than healthy controls. Chronic inpatients with lower levels of physical activity may particularly benefit from rehabilitation interventions aimed at increasing physical fitness.

• Implications for Rehabilitation

• Physical fitness should receive similar attention in the treatment of bipolar disorder and schizophrenia.

• Sedentary patients with a longer duration of illness need additional support in changing lifestyle behaviours.

• Rehabilitation should not only consider cardio-respiratory fitness but also muscular endurance, muscular strength and balance.

     

The meaning of fatigue and tiredness as narrated by women with fibromyalgia and healthy women

1. The aim of this study was to elucidate the meaning of fatigue and tiredness as narrated by women with fibromyalgia (FM) and healthy women. Twenty-five women with FM were interviewed with a narrative approach about the meaning of the lived experience of fatigue and tiredness. A reference group of 25 healthy women was interviewed about the same topic. 2. A phenomenological-hermeneutic method inspired by the French philosopher Ricoeur was used to interpret the interview text. 3. The meaning of fatigue and tiredness was related differently by women with FM and healthy women. The findings are presented in four major themes for women with FM -- the body as a burden, an absent presence, an interfering obstacle and being in hope of alleviation -- and in one major theme for healthy women: needing recovery. 4. Women with FM narrated fatigue as making it obvious that I have a body, instead of I am my body; the lived body becomes urgently present, as an 'it'. Healthy women narrated tiredness as a natural phenomenon when they need recovery and time to rest. 5. The findings are interpreted in the light of the phenomenological work on the lived body by Leder, Toombs and Merleau-Ponty.     

Resistance exercise training improves heart rate variability in women with fibromyalgia

Fibromyalgia (FM) is characterized by generalized muscle pain, low muscle strength and autonomic dysfunction. Heart rate (HR) variability (HRV) is reduced in individuals with FM increasing their risk for cardiovascular morbidity and mortality. We tested the hypothesis that resistance exercise training (RET) improves HRV, baroreflex sensitivity (BRS) and muscle strength in women with FM. Women with FM (n = 10) and healthy controls (n = 9), aged 27-60 years, were compared at baseline. Only women with FM underwent supervised RET 2 days per week for 16 weeks. Baseline and post-training measurements included HRV and spontaneous baroreflex sensitivity (BRS, alpha index) from continuous electrocardiogram and blood pressure (BP) recorded with finger plethysmography during 5 min in the supine position. RR interval, total power, log transformed (Ln) squared root of the standard deviation of RR interval (RMSSD), low-frequency power and BRS were lower (P<0.05), and HR and pulse pressure were higher (P<0.05) in women with FM than in healthy controls. After RET, mean (SEM) total power increased (387 +/- 170 ms(2), P<0.05), RMSSD increased (0.18 +/- 0.08 Ln ms, P<0.05) and Ln of high-frequency power increased (0.54 +/- 0.27 Ln ms(2), P = 0.08) in women with FM. Upper and lower body muscle strength increased by 63% and 49% (P<0.001), and pain perception decreased by 39% in women with FM. There were no changes in BRS, HR and BP after RET. Our study demonstrates that RET improves total power, cardiac parasympathetic tone, pain perception and muscle strength in women with FM who had autonomic dysfunction before the exercise programme.     

Factors influencing BMI classifications of Korean adults

[Purpose] This study aimed to identify factors influencing the BMI classifications of 3,583 Korean adults using data from the fifth Korean National Health and Nutrition Examination Survey. [Subjects and Methods] Measures included lifestyle factors, physiologic factors, perceived health state, stress, subjective body recognition, health-related quality of life, and weight control behavior. [Results] Body perception scores were lower with underweight and higher with overweight and obesity than with a healthy weight. There was a lower proportion of underweight men and a higher proportion of overweight or obese men than women. Instances of Alcohol Use Identification Scores (AUDIT) ≥ 9 were proportionately lower with underweight and more with overweight or obesity relative to an AUDIT score < 9 with healthy weight. Hemoglobin A1c and systolic blood pressure were higher with obesity than with healthy weight. The total cholesterol level was greater with overweight and obesity than with healthy weight. [Conclusion] These results suggest that obesity intervention for adults should be based on age and sex and should include drinking habits and physical activity.Key words: Adults, Body mass index, Obesity     

Fibromyalgia’s Key Symptoms in Normal-Weight,Overweight, and Obese Female Patients

Factors affecting the symptomatology of fibromyalgia (FM) are not fully understood. The aim of the present study was to analyze the relationship of weight status with pain, fatigue, and stiffness in Spanish female FM patients, with special focus on the differences between overweight and obese patients. The sample comprised 177 Spanish women with FM (51.3 ± 7.3 years old). We assessed tenderness (using pressure algometry), pain and vitality using the General Health Short-Form Survey (SF36), and pain, fatigue, morning tiredness, and stiffness using the Fibromyalgia Impact Questionnaire (FIQ). The international criteria for body mass index was used to classify the patients as normal weight, overweight, or obese. Thirty-two percent were normal-weight, 35% overweight, and 32% obese. Both overweight and obese patients had higher levels of pain than normal-weight patients, as assessed by FIQ and SF36 questionnaires and tender point count (p < .01). The same pattern was observed for algometer score, yet the differences were not significant. Both overweight and obese patients had higher levels of fatigue, and morning tiredness, and stiffness (p < .05) and less vitality than normal-weight patients. No significant differences were observed in any of the variables studied between overweight and obese patients. In conclusion, FM symptomatology in obese patients did not differ from overweight patients, whereas normal-weight patients significantly differed from overweight and obese patients in the studied symptoms. These findings suggest that keeping a healthy (normal) weight is not only associated with decreased risk for developing FM but might also be a relevant and useful way of improving FM symptomatology in women.     

Sex Differences in Facial Encoding of Pain

There is substantial evidence that men and women differ in their perception and experience of pain. However, research on sex differences in pain has mainly relied on self-report ratings, whereas little is known about sex differences in facial expression of pain. The aim of the present study was to investigate: 1) whether men and women differ in their facial expressiveness of pain; and 2) whether sex modulates the relationship between self-report and facial pain responses when tonic experimental pain is applied. Forty young and pain-free individuals (male n = 20, female n = 20) were investigated for their subjective and facial responses to tonic heat stimulation at both painful and nonpainful levels. Tonic heat stimulation was tailored to the individual pain threshold. Self-report was assessed via visual analog scales. Facial expression was objectively examined using the Facial Action Coding System. Correlation analyses for the relationship between self-report and facial expression of pain were conducted. Men and women differed neither in self-report ratings nor in facial responses during tonic heat stimulation. However, sex had a considerable impact on the relationship between these variables. Whereas no significant correlations at all were found for men, we obtained several significant correlations in woman. For that reason, future studies investigating the relationship between self-report and nonverbal pain behaviors should consider sex as an important modulating factor. PERSPECTIVE: The findings of the present study suggest that facial responses to pain can be used as estimates of the intensity of subjective pain in women better than in men.