J. Derek Kingsley

Effects of Resistance Training and Chiropractic Treatment in Women with Fibromyalgia

OBJECTIVE The objective of this study was to evaluate resistance training (RES) and RES combined with chiropractic treatment (RES-C) on fibromyalgia (FM) impact and functionality in women with FM. DESIGN The design of the study was a randomized control trial. SETTING Testing and training were completed at the university and chiropractic treatment was completed at chiropractic clinics. PARTICIPANTS Participants (48 +/- 9 years; mean +/- standard deviation) were randomly assigned to RES (n = 10) or RES-C (n = 11). INTERVENTION Both groups completed 16 weeks of RES consisting of 10 exercises performed two times per week. RES-C received RES plus chiropractic treatment two times per week. OUTCOME MEASURES Strength was assessed using one repetition maximum for the chest press and leg extension. FM impact was measured using the FM impact questionnaire, myalgic score, and the number of active tender points. Functionality was assessed using the 10-item Continuous Scale Physical Functional Performance test. Analyses of variance with repeated measures compared groups before and after the intervention. RESULTS Six (6) participants discontinued the study: 5 from RES and 1 from RES-C. Adherence to training was significantly higher in RES-C (92.0 +/- 7.5%) than in RES (82.8 +/- 7.5%). Both groups increased (p < or = 0.05) upper and lower body strength. There were similar improvements in FM impact in both groups. There were no group interactions for the functionality measures. Both groups improved in the strength domains; however, only RES-C significantly improved in the pre- to postfunctional domains of flexibility, balance and coordination, and endurance. CONCLUSIONS In women with FM, resistance training improves strength, FM impact, and strength domains of functionality. The addition of chiropractic treatment improved adherence and dropout rates to the resistance training and facilitated greater improvements in the domains of functionality.

Low-level laser therapy as a treatment for chronic pain.

Chronic pain is defined as pain that persists for greater than 12 weeks (Task-Force, 1994) and currently affects roughly 30% of the population in the United States (Johannes et al., 2010). The most common method for managing chronic pain has traditionally been pharmacological (Nalamachu, 2013). These treatments often include non-steroidal anti-inflammatory drugs (NSAIDS), opioids, acetaminophen, and anticonvulsants (Nalamachu, 2013). Alternative medicine is now also being used more frequently to treat chronic pain and may consist of acupuncture (McKee et al., 2013), Tai Chi (Wang et al., 2010; Wang, 2012), and low-level laser therapy (LLLT) (Enwemeka et al., 2004; Ay et al., 2010). The focus of this manuscript is to highlight the physiological aspects of LLLT, and to discuss its application for those suffering from chronic pain, alone and in combination with exercise. It will also provide justification for the use of LLLT using specific data and case studies from the existing literature which have resulted in positive outcomes for those suffering from chronic pain. The physiological mechanisms of LLLT are not well-understood and the mechanisms tend to be very broad (Yamamoto et al., 1988; Kudoh et al., 1989; Campana et al., 1993; Sakurai et al., 2000; Chow et al., 2007; Moriyama et al., 2009; Cidral-Filho et al., 2014). One hypothesis is that there may be an increase in nociceptive threshold after LLLT resulting in neural blockade, specifically an inhibition of A and C neural fibers (Kudoh et al., 1989; Chow et al., 2007). This inhibition may be mediated by altering the axonal flow (Chow et al., 2007) or by inhibiting neural enzymes (Kudoh et al., 1989). In addition, data suggests an increase in endorphin production (Yamamoto et al., 1988) and opioid-receptor binding via opioid-containing leukocytes with LLLT (Cidral-Filho et al., 2014). LLLT may also mimic the effects of anti-inflammatory drugs by attenuating levels of prostaglandin-2 (PGE2) (Campana et al., 1993) and inhibiting cyclooxygenase-2 (COX-2) (Sakurai et al., 2000). In addition, data have suggested that LLLT may augment levels of nitric oxide, a powerful vasodilator, which would in turn act to increase blood flow and assist with healing (Samoilova et al., 2008; Moriyama et al., 2009; Cidral-Filho et al., 2014; Mitchell and Mack, 2013). While the mechanisms have not been completely explained, it is clear that LLLT may have an analgesic effect. Studies have demonstrated that LLLT may have positive effects on symptomology associated with chronic pain (Fulop et al., 2010; Hsieh and Lee, 2013); however this finding is not universal (Ay et al., 2010). A meta-analysis utilizing 52 effect sizes from 22 articles on LLLT and pain from Fulop et al. (2010) demonstrated an overall effect size of 0.84. This would be classified as a large effect size and suggests a strong inclination for the use of LLLT to reduce chronic pain. Twenty-two studies were utilized with doses ranging from 1 to 30 J/cm2. On the other hand, a meta-analysis from Gam et al. (1993) demonstrated no effect of LLLT on musculoskeletal pain but this study was published over 20 years ago when LLLT was just emerging. More recently data from Ay et al. (2010) have reported no difference in chronic pain compared to placebo using twice weekly treatment 5 days a week for 3 weeks. Treatment consisted of a total energy of 40 J/cm2 (850 nm, 100 mV, a treatment spot area of 0.07 cm2, 4 min over each of the four different points). Taken together, it is hard to assess whether LLLT is an effective modality. However, it is clear that LLLT may be effective in treating chronic pain in many individuals and should not be overlooked as a treatment modality. A systematic review and meta-analysis from 16 randomized control studies on LLLT and neck pain (Chow et al., 2009) interpreted the analysis that LLLT caused an immediate decrease in pain for acute neck pain and up to 22 weeks post in chronic neck pain patients. Recently, in a double blinded placebo control study Leal et al. (2014) reported a decrease pain and increase in function in patients with knee pain. One issue with these meta-analyses is that participants were grouped together, under the heading of chronic pain. However, chronic pain has different manifestations which inhibit the ability to make general observations. Separate subheadings of chronic pain may include but are not limited to chronic neck pain and lower back pain, myofascial pain syndrome, and fibromyalgia. A meta-analysis by Gross et al. (2013) worked to separate out the effect of LLLT on a variety of different conditions. Based on their review, the effect of LLLT on chronic neck pain has a moderate level of evidence for effectiveness when using 830 or 940 nm but not 632.8 nm. However, it was mentioned that the trials investigating chronic neck pain and LLLT failed to blind participants which may limit the application of the data. The authors also included the effect of LLLT on myofascial pain syndrome and reported that the data are mixed and evidence is lacking. In addition, LLLT treatments have been reported to be effective for decreasing pain and increasing function in other chronic pain pathologies including fibromyalgia syndrome (Gur et al., 2002a,b; Armagan et al., 2006; Moore and Demchak, 2012). Studies that examine the use of LLLT combined with exercise seem to have merit, as exercise is a staple of rehabilitation. Interestingly, Djavid et al. (2007) and Gur et al. (2003) both combined LLLT with exercise and each reported no additional effect of exercise in patients with chronic lower back pain. Djavid et al. utilized 27 J/cm2 of total energy (810 nm, 50 mW with an aperture of 0.2211 cm2, 8 points total) while Gur et al. utilized 1 J/cm2 (10 W with an aperature of 10.1 cm2, 4 min per point) for each of the 8 points. Matsutani et al. (2007) combined stretching exercise with LLLT (830 nm, 30 mW with an intensity of 3 J/cm2 over 18 tender points) in 20 women with fibromyalgia. There was no additive effect of combining stretching with LLLT in this study. Both groups reported reductions in pain scores and fatigue. Ultimately, the data are scarce and more are needed to truly understand the implications of LLLT when combined with exercise. What tends to plague research using LLLT as a treatment modality is that there is no standard of care. Studies differ in overall dosage and wavelength which limits the ability to accurately draw conclusions. Currently, there are also no long-term studies that have evaluated LLLT. Pain is a very complex condition that manifests itself in a variety of different forms. Perhaps there is no set standard of care that will encompass everyones needs. However, it is clear that LLLT may be beneficial for many individuals suffering from pain, regardless of the condition that is causing it.

Acute and training effects of resistance exercise on heart rate variability

Heart rate variability (HRV) has been used as a non‐invasive method to evaluate heart rate (HR) regulation by the parasympathetic and sympathetic divisions of the autonomic nervous system. In this review, we discuss the effect of resistance exercise both acutely and after training on HRV in healthy individuals and in those with diseases characterized by autonomic dysfunction, such as hypertension and fibromyalgia. HR recovery after exercise is influenced by parasympathetic reactivation and sympathetic recovery to resting levels. Therefore, examination of HRV in response to acute exercise yields valuable insight into autonomic cardiovascular modulation and possible underlying risk for disease. Acute resistance exercise has shown to decrease cardiac parasympathetic modulation more than aerobic exercise in young healthy adults suggesting an increased risk for cardiovascular dysfunction after resistance exercise. Resistance exercise training appears to have no effect on resting HRV in healthy young adults, while it may improve parasympathetic modulation in middle‐aged adults with autonomic dysfunction. Acute resistance exercise appears to decrease parasympathetic activity regardless of age. This review examines the acute and chronic effects of resistance exercise on HRV in young and older adults.

Arterial Stiffness and Autonomic Modulation After Free-Weight Resistance Exercises in Resistance Trained Individuals.

Abstract Kingsley, JD, Mayo, X, Tai, YL, and Fennell, C. Arterial stiffness and autonomic modulation after free-weight resistance exercises in resistance trained individuals. J Strength Cond Res 30(12): 3373–3380, 2016—We investigated the effects of an acute bout of free-weight, whole-body resistance exercise consisting of the squat, bench press, and deadlift on arterial stiffness and cardiac autonomic modulation in 16 (aged 23 ± 3 years; mean ± SD) resistance-trained individuals. Arterial stiffness, autonomic modulation, and baroreflex sensitivity (BRS) were assessed at rest and after 3 sets of 10 repetitions at 75% 1-repetition maximum on each exercise with 2 minutes of rest between sets and exercises. Arterial stiffness was analyzed using carotid-femoral pulse wave velocity (cf-PWV). Linear heart rate variability (log transformed [ln] absolute and normalized units [nu] of low-frequency [LF] and high-frequency [HF] power) and nonlinear heart rate complexity (Sample Entropy [SampEn], Lempel-Ziv Entropy [LZEn]) were measured to determine autonomic modulation. BRS was measured by the sequence method. A 2 × 2 repeated measures analysis of variance (ANOVA) was used to analyze time (rest, recovery) across condition (acute resistance exercise, control). There were significant increases in cf-PWV (p = 0.05), heart rate (p = 0.0001), normalized LF (LFnu; p = 0.001), and the LF/HF ratio (p = 0.0001). Interactions were also noted for ln HF (p = 0.006), HFnu (p = 0.0001), SampEn (p = 0.001), LZEn (p = 0.005), and BRS (p = 0.0001) such that they significantly decreased during recovery from the resistance exercise compared with rest and the control. There was no effect on ln total power, or ln LF. These data suggest that a bout of resistance exercise using free-weights increases arterial stiffness and reduces vagal activity and BRS in comparison with a control session. Vagal tone may not be fully recovered up to 30 minutes after a resistance exercise bout.

The effect of motor imagery and static stretching on anaerobic performance in trained cyclists.

Abstract Kingsley, JD, Zakrajsek, RA, Nesser, TW, and Gage, MJ. The effect of motor imagery and static stretching on anaerobic performance in trained cyclists. J Strength Cond Res 27(1): 265–269, 2013—Athletes perform many different protocols as part of their warm-up routine before competition. Stretching has been suggested to decrease force and power production, whereas motor imagery (MI), the visualization of simple or complex motor activities in the absence of physical movement, may increase force and power production in young healthy individuals. Few studies have investigated either of these in trained individuals. No studies have compared the effects of static stretching (SS) with MI on anaerobic performance in trained cyclists. The purpose of this study was to examine the effects of SS compared with MI and quiet rest (QR) on anaerobic performance in trained cyclists. Thirteen trained cyclists (9 men: 4 women; aged 21 ± 2 years) were assessed for height (1.76 ± 0.07 m), weight (73.4 ± 13 kg), % body fat (10.8 ± 6.2%), and maximal oxygen consumption (V[Combining Dot Above]O2max of 42.0 ± 5.6 ml·kg−1·min−1) on a cycle ergometer. The participants performed 3 randomized sessions consisting of cycling for 30 minutes at 65% of V[Combining Dot Above]O2max before undergoing 16 minutes of SS, MI, or QR followed by an anaerobic performance test. The SS consisted of 3 sets of 30-second stretches of the hamstrings, quadriceps, hip flexors, and piriformis. Imagery was based on the physical, environmental, task, learning, emotion, and perspective approach and was conducted by a trained technician. Both relative and absolute powers, and peak revolutions per minute, were quantified using the Wingate anaerobic threshold test. No significant interactions existed among SS, MI, and QR for relative peak power, absolute peak power, or peak RPM. In disagreement with current literature, this study suggests that neither SS nor a single session of MI immediately affect anaerobic performance in trained cyclists. If an event is <30 seconds, then SS or MI may not affect performance.

Free-weight resistance exercise on pulse wave reflection and arterial stiffness between sexes in young, resistance-trained adults

Abstract We sought to determine the sex-specific effects of an acute bout of free-weight resistance exercise (RE) on pulse wave reflection (aortic blood pressures, augmentation index (AIx), AIx at 75 bpm (AIx@75), augmentation pressure (AP), time of the reflected wave (Tr), subendocardial viability ratio (SEVR)), and aortic arterial stiffness in resistance-trained individuals. Resistance-trained men (n = 14) and women (n = 12) volunteered to participate in the study. Measurements were taken in the supine position at rest, and 10 minutes after 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift. A 2 × 2 × 2 ANOVA was used to analyse the effects of sex (men, women) across condition (RE, control) and time (rest, recovery). There were no differences between sexes across conditions and time. There was no effect of the RE on brachial or aortic blood pressures. There were significant condition × time interactions for AIx (rest: 12.1 ± 7.9%; recovery: 19.9 ± 10.5%, p = .003), AIx@75 (rest: 5.3 ± 7.9%; recovery: 24.5 ± 14.3%, p = .0001), AP (rest: 4.9 ± 2.8 mmHg; recovery: 8.3 ± 6.0 mmHg, p = .004), and aortic arterial stiffness (rest: 5.3 ± 0.6 ms; recovery: 5.9 ± 0.7 ms, p = .02) with significant increases during recovery from the acute RE. There was also a significant condition × time for time of the reflected wave (rest: 150 ± 7 ms; recovery: 147 ± 9 ms, p = .02) and SEVR (rest: 147 ± 17%; recovery: 83 ± 24%, p = .0001) such that they were reduced during recovery from the acute RE compared to the control. These data suggest that an acute bout of RE increases AIx, AIx@75, and aortic arterial stiffness similarly between men and women without significantly altering aortic blood pressures.

Acute resistance exercise using free weights on aortic wave reflection characteristics

Aortic wave reflection characteristics such as the augmentation index (AIx), wasted left ventricular pressure energy (ΔEw) and aortic haemodynamics, such as aortic systolic blood pressure (ASBP), strongly predict cardiovascular events. The effects of acute resistance exercise (ARE) using free‐weight exercises on these characteristics are unknown. Therefore, we sought to determine the effects of acute free‐weight resistance exercise on aortic wave reflection characteristics and aortic haemodynamics in resistance‐trained individuals. Fifteen young, healthy resistance‐trained (9 ± 3 years) individuals performed two randomized sessions consisting of an acute bout of free‐weight resistance exercise (ARE) or a quiet control (CON). The ARE consisted of three sets of 10 repetitions at 75% one repetition maximum for squat, bench press and deadlift. In CON, the participants rested in the supine position for 30 min. Measurements were made at baseline before sessions and 10 min after sessions. A two‐way ANOVA was used to compare the effects of condition across time. There were no significant interactions for aortic or brachial blood pressures. Compared to rest, there were significant increases in augmentation pressure (rest: 5·7 ± 3·0 mmHg; recovery: 10·4 ± 5·7 mmHg, P = 0·002), AIx (rest: 116·8 ± 4·2%; recovery: 123·2 ± 8·4%, P = 0·002), AIx normalized at 75 bpm (rest: 5·2 ± 7·6%; recovery: 27·3 ± 13·2%, P<0·0001), ΔEw (rest: 1215 ± 674 dynes s cm−2; recovery: 2096 ± 1182 dynes s cm−2, P = 0·008), and there was a significant decrease in transit time of the reflected wave (rest: 150·7 ± 5·8 ms; recovery 145·5 ± 5·6 ms, P<0·001) during recovery from ARE compared to CON. These data suggest that ARE using free‐weight exercises may have no effect on aortic and brachial blood pressure but may significantly alter aortic wave reflection characteristics.

Exercise Type Affects Cardiac Vagal Autonomic Recovery After a Resistance Training Session.

Abstract Mayo, X, Iglesias-Soler, E, Fariñas-Rodríguez, J, Fernández-del-Olmo, M, and Kingsley, JD. Exercise type affects cardiac vagal autonomic recovery after a resistance training session. J Strength Cond Res 30(9): 2565–2573, 2016—Resistance training sessions involving different exercises and set configurations may affect the acute cardiovascular recovery pattern. We explored the interaction between exercise type and set configuration on the postexercise cardiovagal withdrawal measured by heart rate variability and their hypotensive effect. Thirteen healthy participants (10 repetitions maximum [RM] bench press: 56 ± 10 kg; parallel squat: 91 ± 13 kg) performed 6 sessions corresponding to 2 exercises (Bench press vs. Parallel squat), 2 set configurations (Failure session vs. Interrepetition rest session), and a Control session of each exercise. Load (10RM), volume (5 sets), and rest (720 seconds) were equated between exercises and set configurations. Parallel squat produced higher reductions in cardiovagal recovery vs. Bench press (p = 0.001). These differences were dependent on the set configuration, with lower values in Parallel squat vs. Bench press for Interrepetition rest session (1.816 ± 0.711 vs. 2.399 ± 0.739 Ln HF/IRR2 × 104, p = 0.002), but not for Failure session (1.647 ± 0.904 vs. 1.808 ± 0.703 Ln HF/IRR2 × 104, p > 0.05). Set configuration affected the cardiovagal recovery, with lower values in Failure session in comparison with Interrepetition rest (p = 0.027) and Control session (p = 0.022). Postexercise hypotension was not dependent on the exercise type (p > 0.05) but was dependent on the set configuration, with lower values of systolic (p = 0.004) and diastolic (p = 0.011) blood pressure after the Failure session but not after an Interrepetition rest session in comparison with the Control session (p > 0.05). These results suggest that the exercise type and an Interrepetition rest design could blunt the decrease of cardiac vagal activity after exercise while exercising to muscular failure may contribute to the onset of postexercise hypotension.

High-intensity interval cycling exercise on wave reflection and pulse wave velocity.

Abstract Kingsley, JD, Tai, YL, Vaughan, J, and Mayo, X. High-intensity interval cycling exercise on wave reflection and pulse wave velocity. J Strength Cond Res 31(5): 1313–1320, 2017—The purpose of this study was to assess the effects of high-intensity exercise on wave reflection and aortic stiffness. Nine young, healthy men (mean ± SD: age: 22 ± 2 years) participated in the study. The high-intensity interval cycling exercise consisted of 3 sets of Wingate Anaerobic Tests (WATs) with 7.5% of bodyweight as resistance and 2 minutes of rest between each set. Measurements were taken at rest and 1 minute after completion of the WATs. Brachial and aortic blood pressures, as well as wave reflection characteristics, were measured through pulse wave analysis. Aortic stiffness was assessed through carotid-femoral pulse wave velocity (cfPWV). A repeated-measures analysis of variance was used to investigate the effects of the WATs on blood pressure and vascular function across time. There was no change in brachial or aortic systolic pressure from rest to recovery. There was a significant (p ⩽ 0.05) decrease in brachial diastolic pressure (rest: 73 ± 6 mm Hg; recovery: 67 ± 9 mm Hg) and aortic diastolic pressure (rest: 75 ± 6 mm Hg; recovery: 70 ± 9 mm Hg) from rest to recovery. In addition, there was no significant change in the augmentation index (rest: 111.4 ± 6.5%; recovery: 109.8 ± 5.8%, p = 0.65) from rest to recovery. However, there was a significant (p ⩽ 0.05) increase in the augmentation index normalized at 75 b·min−1 (rest: 3.29 ± 9.82; recovery 21.21 ± 10.87) during recovery compared with rest. There was no change in cfPWV (rest: 5.3 ± 0.8 m·s−1; recovery: 5.7 ± 0.5m·s−1; p = 0.09) in response to the WAT. These data demonstrate that high-intensity interval cycling exercise with short rest periods has a nonsignificant effect on vascular function.

Pulse wave reflection responses to bench press with and without practical blood flow restriction

Resistance exercise is recommended to increase muscular strength but may also increase pulse wave reflection. The effect of resistance exercise combined with practical blood flow restriction (pBFR) on pulse wave reflection is unknown. The purpose of this study was to evaluate the differences in pulse wave reflection characteristics between bench press with pBFR and traditional high-load bench press in resistance-trained men. Sixteen resistance-trained men participated in the study. Pulse wave reflection characteristics were assessed before and after low-load bench press with pBFR (LL-pBFR), traditional high-load bench press (HL), and a control (CON). A repeated-measures ANOVA was used to evaluate differences in pulse wave reflection characteristics among the conditions across time. There were significant (p ≤ 0.05) interactions for heart rate, augmentation index, augmentation index normalized at 75 bpm, augmentation pressure, time-tension index, and wasted left ventricular energy such that they were increased after LL-pBFR and HL compared with rest and CON, with no differences between LL-pBFR and HL. Aortic pulse pressure (p < 0.001) was elevated only after LL-pBFR compared with rest. In addition, there was a significant (p ≤ 0.05) interaction for aortic diastolic blood pressure (BP) such that it was decreased after LL-pBFR compared with rest and CON but not HL. The subendocardial viability ratio and diastolic pressure-time index were significantly different between LL-pBFR and HL compared with rest and CON. There were no significant interactions for brachial systolic or diastolic BP, aortic systolic BP, or time of the reflected wave. In conclusion, acute bench press resistance exercise significantly altered pulse wave reflection characteristics without differences between LL-pBFR and HL.