Publications

Abstract

  • High-Intensity interval training reduces transcriptomic age: A randomized controlled trial (10/2023)
  • High-Intensity Interval Training and Biological Age   (02/2023)
  • Gender and Intermittent Fasting (10/2022)
  • Age, Vitamin C, Serum Creatinine, White Blood Cell Count, and Glucosuria are Significantly Associated with Time-to-Death (10/2022)
  • The efficacy of sustained heat treatment on Delayed onset muscle Soreness .  (10/2016)
  • Berk L, Cavalcanti P, Soni J, & Varadarajan S. (2012). Stress Hormone Biomarker Response in Fit and Unfit Premenopausal Women to One-Hour Aerobic Run. Medicine and Science in Sports and Exercise, 44, 743-743. (05/2012)
  • Berk L, Cavalcanti P, & Bains G. (2012). EEG brain wave band differentiation during a eustress state of humor associated mirthful laughter compared to a distress state. Faseb Journal, 26, . (04/2012)
  • Cavalcanti P R, Campos T F, Berk L S, & Araujo J F. (2011). Correlation of Circadian and Homeostatic Changes in the Sleep-Wake Pattern with Quality of Life in Chronic Stroke Patients. Stroke, 42(3), E324-E325. (03/2011)
  • Schneider L E, Prowse M, Berk L, Daher N S, & Haddock B. (2011). THE EFFECT OF A ONE-HOUR AEROBIC RUN ON 25-OH VITAMIN D LEVELS IN TRAINED AND UNTRAINED PREMENOPAUSAL WOMEN. Journal of Investigative Medicine, 59(1), 107-108. (01/2011)
  • (PEER REVIEWED) Berk, L., Prowse, M., Bains, G., Batt, J., Petrofsky, J., Daher, N., Danner, H., Ludeman, L., Lahman, M., Tan, S., and Berk, D. (2010) Humor-associated laughter affects appetite hormones. 2010 Experimental Biology meeting abstracts, Abstract #996.1; http://www.fasebj.org/cgi/gca?SEARCHID=1&VOLUME=24&ISSUE=1_MeetingAbstracts&FIRSTINDEX=0&hits=20&RESULTFORMAT=&gca=24%2F1_MeetingAbstracts%2F996.1&sendit=Get+All+Checked+Abstract%28s%29. Accessed April 27, 2010. A "hot pick" presentation of the American Physiological Society; http://www.the-aps.org/press/releases/10/12.htm. (07/2009 - 06/2010)
  • (PEER REVIEWED) Mirthful laughter, as adjunct therapy in diabetic care, increases HDL cholesterol and attenuates inflammatory cytokines and hs-CRP Lee S. Berk, DrPH, Stanley Tan, MD, Linda Tan, MD, Dottie Berk, RN Dept of Physical Therapy, School of Allied Health and Dept of Pathology, School of Medicine, Loma Linda University, Loma Linda, CA 92350 and OakCrest  Health Research Institute, Loma Linda, CA   Presented at the FASEB 2009 (Experimental Biology 2009), American Physiological Society Section, April 20-25, 2009, New Orleans, LA (07/2009 - 06/2010)
  • (PEER REVIEWED) THE EFFECT OF PERCEIVED STRESS AND RELIGIOSITY AS A MODULATOR OF HS-CRP, A RISK FACTOR FOR CVD Bruce Nelson1, Sally Fontamillas Shaw1, Lee S. Berk 2,3, Michelle Prowse2, Dana King4   1Glendale Adventist Medical Center, Schools of 2Allied Health Professions, Dept. of PT & 3Medicine, Dept of Pathology, Loma Linda University, 4Medical University of South Carolina, Charleston, SC     Presented at the 2nd Annual Meeting of the Society for Spirituality, Theology and Health. Duke University, Durham, NC. June 25-27, 2009.  (not previously documented in faculty report) (07/2009 - 06/2010)
  • (PEER REVIEWED) Laughercise: Health Benefits Similar to Exercise Lowers Cholesterol and Systolic Blood Pressure Lee S. Berk1,2, Michelle Prowse1, Jerrold S. Petrofsky1, Jennifer Batt3, Michael Laymon3 Gurinder S. Bains1 , Noha Daher1 & Dottie Berk4 Schools of 1Allied Health Professions, Dept of Physical Therapy & 2Medicine, Dept. of Pathology, Loma Linda University, Loma Linda, CA,  3School of Behavioral and Applied Sciences, Azusa Pacific University, Azusa, CA. Presented at the Association for Psychological Sciences, San Francisco, May 22-25, 2009. (not previously documented in faculty report) (07/2009 - 06/2010)
  • (PEER REVIEWED) Perceived Stress, Early Parental Care and Religiosity- Modulators for Cardiovascular Disease Risk. Lee S. Berk 2,3, Bruce Nelson1, Sally Fontamillas Shaw1, Michelle Prowse2, Dana King4   1Glendale Adventist Medical Center, Dept of Physical Therapt, 2School of Allied Health Professions & 3Dept of Pathology School of Medicine, Loma Linda University, 4Medical University of South Carolina, Charleston, SC             Presented at the Association for Psychological Science, San Francisco, CA, May 22-25, 2009.  (not previously reported in faculty report)  (07/2009 - 06/2010)
  • (PEER REVIEWED) THE EFFECT OF PERCEIVED STRESS AND RELIGIOSITY AS A MODULATOR OF HS-CRP, A RISK FACTOR FOR CVD     Sally F. Shaw, DrPH, Bruce Nelson, MA, Community Services, Glendale Adventist  Medical Center, Glendale, CA, Lee S. Berk, DrPH, Dept. Physical Therapy, School of Allied Health Professions and Dept. Pathology, School of Medicine, Michelle A. Prowse, MS, School of Allied Health Professions, Loma Linda University, Loma Linda, CA, Dana E. King, MD, Family Medicine, Medical University of South Carolina, Charleston, SC.  Presented at the American Psychosomatic Medicine Meetings, Chicago, IL, March 4-7, 2009.  (not previously reported in faculty report) (07/2009 - 06/2010)
  • (PEER REVIEWED) Charasuraisin, C, Berk, L, Petrofsky, JS, Montgomery, S., Shavlik, D., Hubbard,   R (2008) Can a Single High-Fat Meal Impair Endothelial and Autonomic Function?, #2008-LB-4930-Diabetes.   Presented at the American Diabetes Association Meeting, June, 2008, San Francisco, CA  (not previously reported in faculty report) (07/2009 - 06/2010)
  • (PEER REVIEWED) Cortisol and Catecholamines decrease are associated with the behavior of perceptual anticipation of a mirthful laughter humor experience. Berk LS, Tan SA, Berk DE           Presentation at FASEB 2008 Meetings, April 2008, San Diego, CA   (not previously reported in faculty report)   (07/2009 - 06/2010)
  • (PEER REVIEWED) Mirthful Laughter, as Adjunct Therapy in Diabetic Care, Attenuates Catecholamines, Inflammatory Cytokines, C - reactive protein, and Myocardial Infarction Occurrence. Berk, LS, Tan, LG, and Tan, SA       Presentation at FASEB 2008 Meetings, April 2008, San Diego, CA   (not previously documented in faculty report)   (07/2009 - 06/2010)
  • (PEER REVIEWED) Linda G. Tan, MD, Lee S. Berk, DrPH, Stanley A. Tan, MD, PhD. "Combined Effects of Rosuvastatin and Pioglitazone in Attenuating INF-gamma, TNF-alpha, IL-6, C-Reactive protein, and Increasing IL-4, May Provide Cardioprotection For Patients with Diabetes.." American College of Chest Physicians Annual Meeting unknown.unknown (2007): unknown-unknown. (10/2007)
  • (PEER REVIEWED) L.G. Tan, S.A. Tan, L.S. Berk. "Mirthful Laughter, as Adjunct Therapy in Diabetic Care, Attenuates Catecholamines, Inflammatory Cytokines, C - reactive protein, and Myocardial Infarction Occurrence." European Preventive Cardiology Meeting NA.NA (2007): NA-NA. (04/2007)
  • (PEER REVIEWED) Stanley Tan, MD, PhD, Linda Giles Tan, MD, Lee Berk, DrPH, MPH. "Atorvastatin and Pioglitazone Effects on Inflammatory Cytokines and Lipids." AACE NA.NA (2007): NA-NA. (04/2007)
  • 4.L.G. Tan, S.A. Tan and L.S. Berk. Pravastatin and Rosiglitazone May Attenuate Coronary Artery Disease by Decreasing Interferon-gamma, Tumor Necrosis Factor- alpha, Interleukin-6, Macrophage Chemotactic Protein-1, C-Reactive Protein, and Increasing Interleukin-4.  In Book: New Horizons in Coronary Artery Disease - Proceedings of the 7th International Congress on Coronary Artery Disease.  Editor(s): Lewis B.S., Halon D.A., Flugelman M.Y. Year of Publication: 2007;  (2007)
  • (PEER REVIEWED) Bruce Nelson, Robert Nicoloff, AnneMarie Loes-Gomez, Lee Berk, and James Westengard. "Lessons Learned: Utilization of prescreening surveys and glucose tolerance testing for large-scale diabetes risk screenings." APHA 134th Annual Meeting Abstracts NA.NA (2006): NA-NA. (11/2006)
  • (PEER REVIEWED) Linda G. Tan, MD, Lee S. Berk, DrPH, Stanley A. Tan, MD, PhD. "Combined Effects of Rosuvastatin and Pioglitazone in Attenuating INF-gamma, TNF-alpha, IL-6, C-Reactive protein, and Increasing IL-4, May Provide Cardioprotection For Patients with Diabetes." ACCP NA.NA (2006): NA-NA. (10/2006)

Scholarly Journals--Published

  • High-Intensity interval training reduces transcriptomic age: A randomized controlled trial (04/2023)
  • Sahba, K., Berk, L., Bussell, M., Lohman, E., Zamora, F., & Gharibvand, L. (2022). Treating peripheral neuropathy in individuals with type 2 diabetes mellitus with intraneural facilitation: a single-blind randomized control trial. The Journal of international medical research, 50(8), 3000605221109390. https://doi.org/10.1177/03000605221109390 (08/2022) (link)
  • Dos Santos, H., Raphael, J. C., Reis, W. P., Gaio, J., Berk, L. S., Bellinger, D. L., & Lee, J. W. (2019). The Association between Affect and Biomarkers of Stress and Inflammation in Healthy Seventh-Day Adventists. Advances in mind-body medicine, 33(3), 12–20. (06/2019)
  • Mineyama, Y., Hyder Ferry, L., Arechiga, A., Dos Santos, H., & Berk, L. (2019). The Effect of a Tobacco Dependence Treatment Program With Stress Management Through Mindfulness Technique Training in US Veterans. Advances in mind-body medicine, 33(2), 12–17. (06/2019)
  • Lohman, T., Bains, G., Berk, L., & Lohman, E. (2021). Predictors of Biological Age: The Implications for Wellness and Aging Research. Gerontology & geriatric medicine, 7, 23337214211046419. https://doi.org/10.1177/23337214211046419 (01/2019) (link)
  • Cavalcanti-Ferreira, P., Berk, L., Daher, N., Campus, T., Araujo, J., Petrofsky, J., & Lohman, E. (2018). A nonparametric methodological analysis of rest-activity rhythm in type 2 diabetes. Sleep science (Sao Paulo, Brazil), 11(4), 281–289. https://doi.org/10.5935/1984-0063.20180044   (08/2018) (link)
  • Moldovan C P, Weldon A J, Daher N S, Schneider L E, Bellinger D L, . . . Peters W R. (2016). Effects of a Meal Replacement System Alone or in Combination with Phentermine on Weight Loss and Food Cravings. Obesity, 24(11), 2344-2350. Objective: To examine the effects of phentermine combined with a meal replacement program on weight loss and food cravings and to investigate the relationship between food cravings and weight loss. Methods: In a 12-week randomized, double-blind, placebo-controlled clinical trial, 77 adults with obesity received either phentermine or placebo. All participants were provided Medifast VR meal replacements, were instructed to follow the Take Shape for Life VR Optimal Weight 5&1 Plan for weight loss, and received lifestyle coaching in the Habits of Health program. The Food Craving Inventory and the General Food Cravings State and Trait Questionnaires were used to measure food cravings. Results: The phentermine group lost 12.1% of baseline body weight compared with 8.8% in the placebo group. Cravings for all food groups decreased in both groups; however, there was a greater reduction in cravings for fats and sweets in the phentermine group compared with the placebo group. Percent weight loss correlated significantly with reduced total food cravings (r=0.332, P = 0.009), cravings for sweets (r = 0.412, P < 0.000), and state food cravings (r = 0.320, P = 0.007). Conclusions: Both phentermine combined with a meal replacement program and meal replacements alone significantly reduced body weight and food cravings; however, the addition of phentermine enhanced these effects. (11/2016) (link)
  • Petrofsky J, Berk L, Bains G, Khowailed I A, Lee H, & Laymon M. (2016). The Efficacy of Sustained Heat Treatment on Delayed-Onset Muscle Soreness. Clin J Sport Med, , . OBJECTIVE: To assess the impact of heat applied for 8 hours immediately after or 24 hours after exercise on delayed-onset muscle soreness (DOMS) in large skeletal muscle groups measured by subjective and objective means. DESIGN: Cross-sectional repeated measure design study. SETTING: Research laboratory. SUBJECTS: Three groups of 20 subjects, age range 20 to 40 years. INTERVENTION: Squats were conducted in three 5-minute bouts to initiate DOMS; 3 minutes of rest separated the bouts. One group had heat applied immediately after exercise, and a second group had heat applied 24 hours after exercise. A third group was the control group where no heat was applied. MAIN OUTCOME MEASURES: Visual analog pain scales, muscle strength of quads, range of motion of quads, stiffness of quads (Continuous Passive Motion machine), algometer to measure quadriceps soreness, and blood myoglobin. RESULTS: The most significant outcome was a reduction in soreness in the group that had low-temperature heat wraps applied immediately after exercise (P < 0.01). There was benefit to applying heat 24 hours after exercise, but to a smaller extent. This was corroborated by myoglobin, algometer, and stiffness data. CONCLUSIONS: Low-level continuous heat wraps left for 8 hours just after heavy exercise reduced DOMS in the population tested as assessed by subjective and objective measures. CLINICAL RELEVANCE: Although cold is commonly used after heavy exercise to reduce soreness, heat applied just after exercise seems very effective in reducing soreness. Unlike cold, it increases flexibility of tissue and tissue blood flow. For joint, it is still probably better to use cold to reduce swelling. (07/2016) (link)
  • Bains Gurinder Singh, Berk Lee S, Lohman Everett, Daher Noha, Petrofsky Jerrold, Schwab Ernie, & Deshpande Pooja. (2015). Humorâ??s Effect on Short-term Memory in Healthy and Diabetic Older Adults. Alternative Therapies in Health & Medicine, 21(3), 16-25. Context â?¢ With aging, the detrimental effects of stress can impair a personâ??s ability to learn and sustain memory. Humor and its associated mirthful laughter can reduce stress by decreasing the hormone cortisol. Chronic release of cortisol can damage hippocampal neurons, leading to impairment of learning and memory. Objectives â?¢ The study intended to examine the effect of watching a humor video on short-term memory in older adults. Design â?¢ The research team designed a randomized, controlled trial. Setting â?¢ The study took place at Loma Linda University in Loma Linda, CA, USA. Participants â?¢ The study included 30 participants: 20 normal, healthy, older adultsâ??11 males and 9 femalesâ?? and 10 older adults with type 2 diabetes mellitus (T2DM)â?? 6 males and 4 females. Intervention â?¢ The study included 2 intervention groups of older adults who viewed humorous videos, a healthy group (humor group), aged 69.9 ± 3.7 y, and the diabetic group, aged 67.1 ± 3.8 y. Each participant selected 1 of 2 humorous videos that were 20 min in length, either a Red Skeleton comedy or a montage of Americas Funniest Home Videos. The control group, aged 68.7 ± 5.5 y, did not watch a humor video and sat in quiescence. Outcome Measures â?¢ A standardized, neuropsychological, memory-assessment tool, the Rey Auditory Verbal Learning Test (RAVLT), was used to assess the following abilities: (1) learning, (2) recall, and (3) visual recognition. The testing occurred twice, once before (RAVLT1) and once after (RAVLT2) the humorous video for the humor and diabetic groups, and once before (RAVLT1) and once after (RAVLT2) the period of quiescence for the control group. At 5 time points, measurements of salivary cortisol were also obtained. The Kruskal-Wallis test was used to measure significance of the data based on the 3 groups. Results â?¢ In the humor, diabetic, and control groups, (1) learning ability improved by 38.5%, 33.4%, and 24.0%, respectively (P= .025); (2) delayed recall improved by 43.6%, 48.1%, and 20.3%, respectively (P=.064); and (3) visual recognition increased by 12.6%, 16.7%, and 8.3%, respectively (P = .321). For levels of salivary cortisol, the research team found significant and borderline decreases for the humor group between baseline and (1) post-RAVLT1 (P=.047), (2) postvideo (P=.046), and (3) post-RAVLT2 (P=.062). The diabetic group showed significant decreases between baseline and (1) post-RAVLT1 (P=.047), (2) postvideo (P=.025), and (3) post-RAVLT2 (P=.034). The study found no significant changes for the control group. Conclusion â?¢ The research findings supported potential clinical and rehabilitative benefits for humor that can be applied to whole-person wellness programs for older adults. The cognitive componentsâ??learning ability and delayed recallâ??become more challenging as individuals age and are essential to older adults for providing a high quality of life: mind, body, and spirit. Because older adults can experience age-related memory deficits, complementary, enjoyable, and beneficial humor therapies should be implemented for them. [ABSTRACT FROM AUTHOR] Copyright of Alternative Therapies in Health & Medicine is the property of PH Innovisions Journal Operating LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) (2015) (link)
  • Koenig Harold G, Pearce Michelle J, Nelson Bruce, Shaw Sally F, Robins Clive J, . . . King Michael B. (2015). Religious vs conventional cognitive behavioral therapy for major depression in persons with chronic medical illness: A pilot randomized trial. Journal of Nervous and Mental Disease, 203(4), 243-251. We examine the efficacy of conventional cognitive behavioral therapy (CCBT) versus religiously integrated CBT (RCBT) in persons with major depression and chronic medical illness. Participants were randomized to either CCBT (n = 67) or RCBT (n = 65). The intervention in both groups consisted of ten 50-minute sessions delivered remotely during 12 weeks (94% by telephone). Adherence to treatment was similar, except in more religious participants in whom adherence to RCBT was slightly greater (85.7% vs. 65.9%, p = 0.10). The intention-to-treat analysis at 12 weeks indicated no significant difference in outcome between the two groups (B = 0.33; SE, 1.80; p = 0.86). Response rates and remission rates were also similar. Overall religiosity interacted with treatment group (B = â??0.10; SE, 0.05; p = 0.048), suggesting that RCBT was slightly more efficacious in the more religious participants. These preliminary findings suggest that CCBT and RCBT are equivalent treatments of major depression in persons with chronic medical illness. Efficacy, as well as adherence, may be affected by client religiosity. (PsycINFO Database Record (c) 2015 APA, all rights reserved). (journal abstract) (2015) (link)
  • Stark Jill, Petrofsky Jerrold, Berk Lee, Bains Gurinder, Chen Shijie, & Doyle Geraldine. (2014). Continuous Low-Level Heatwrap Therapy Relieves Low Back Pain and Reduces Muscle Stiffness. Physician and Sportsmedicine, 42(4), 39-48. Background: Low back pain is a common and costly health care problem. This pilot study evaluated the sensitivity of the 2-stopwatch and Paris plinth methodologies for assessing time-to- onset of pain relief and flexibility, respectively, with continuous, low-level heatwrap therapy. Research Design and Methods: Subjects aged 18 to 55 years with at least moderate baseline acute low back pain were randomly assigned to either heatwrap or oral placebo for 8 hours. Unheated wrap (sham) and oral ibuprofen were included for blinding purposes only. Results: Sixty-one subjects were randomly assigned to either heatwrap (n = 26), oral placebo (n = 25), sham wrap (n = 5), or oral ibuprofen (n = 5). Median time to confirmed first perceptible pain relief and to meaningful pain relief were significantly shorter for the heatwrap group compared with those assigned to oral placebo (96.5 vs. > 240.0 min and 215.7 vs. > 240.0 min, respectively; P < 0.05 for both). Among subjects receiving the heatwrap, 53.8% reported first perceptible and meaningful relief, compared with 28.0% receiving oral placebo. Subjective measures of pain relief, back stiffness, and global evaluation were more sensitive in detecting treatment differences than the plinth assessments of flexibility, range of motion, and pain. Three adverse events were reported as mild in severity and considered unrelated to study treatment. Conclusions: The 2-stopwatch methodology is a viable approach for assessing onset of analgesia in low back pain; however, the plinth may not be a reliable method for assessing flexibility. Consistent with published studies involving much larger sample sizes, the heatwrap provided significantly faster and sustained pain relief than oral placebo in subjects with acute low back pain. (11/2014) (link)
  • Bains Gurinder, Berk Lee, Daher Noha, Lohman Everett, Petrofsky Jerrold, Schwab Ernie, & Deshpande Pooja. (2014). Effectiveness of humor on short-term memory function and cortisol levels in age matched elderly and diabetic subjects vs control group. FASEB Journal, 28(1), . (04/2014)
  • Berk Lee, Alphonso Clarice, Thakker Neha, & Nelson Bruce. (2014). Humor similar to meditation enhances EEG power spectral density of gamma wave band activity (31-40Hz) and synchrony. FASEB Journal, 28(1), . (04/2014)
  • Lee Haneul, Petrofsky Jerrold, Daher Noha, Berk Lee, & Laymon Michael. (2014). Differences in anterior cruciate ligament elasticity and force for knee flexion in women: oral contraceptive users versus non-oral contraceptive users. Eur J Appl Physiol, 114(2), 285-294. Eighty-two percent of sexually active women aged 15-44 have used oral contraceptive pills (OCP) in the United States. The OCP, an exogenous source of synthetic forms of steroid hormones, prevents ovulation. Hormone changes during the menstrual cycle (MC) are believed to have an impact on anterior cruciate ligament (ACL) laxity due to estrogen. Because the estrogen receptor β resides on human connective tissue, OCP may have potential impact on tendon and ligament synthesis, structure, and biomechanical properties. Temperature has also been known to have an effect on tissue elasticity. Therefore, the purpose of this study was to investigate the differences in ACL elasticity, force to flex the knee (FFK), and knee flexion-extension hysteresis (KFEH) between OCP users and non-OCP users. To investigate these changes, two different knee temperatures were measured. Nineteen young females were divided into two groups: OCP users and non-OCP users. Blood for estradiol serum concentration (E2) was taken before beginning the tests. ACL elasticity, FFK, and KFEH were assessed both at ambient temperature (22 °C) and after 38 °C warming of the leg to stabilize tissue temperature. Assessments were performed four times during the MC. Throughout the MC, ACL elasticity, FFK, and KFEH fluctuated in non-OCP users, but not in OCP users. At ambient temperature, ACL elasticity was significantly lower and FFK and KFEH were significantly higher in OCP users than non-OCP users ( p < 0.05). But, no significant differences in FFK and KFEH between the two groups were found after warming to 38 °C. [ABSTRACT FROM AUTHOR] Copyright of European Journal of Applied Physiology is the property of Springer Science & Business Media B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) (2014) (link)
  • Son D. Jacquart, Helen H. Marshak, Hildemar Dos Santos, Sen M. Luu, Lee S. Berk, Paul T. McMahon, Matt Riggs. The effects of simultaneous exercise and psychotherapy on depressive symptoms in inpatient, psychiatric older adults. Adv Mind Body Med. 2014 Fall; 28(4): 8–17. (2014)
  • Petrofsky J, Berk L, Bains G, Khowailed I A, Hui T, . . . Lee H. (2013). Moist heat or dry heat for delayed onset muscle soreness. J Clin Med Res, 5(6), 416-25. BACKGROUND: Heat is commonly used in physical therapy following exercise induced delayed onset muscle soreness (DOMS). Most heat modalities used in a clinical setting for DOMS are only applied for 5 to 20 minutes. This minimal heat exposure causes little, if any, change in deep tissue temperature. For this reason, long duration dry chemical heat packs are used at home to slowly and safely warm tissue and reduce potential heat damage while reducing pain associated from DOMS. Clinically, it has been shown that moist heat penetrates deep tissue faster than dry heat. Therefore, in home use chemical moist heat may be more efficacious than dry heat to provide pain relief and reduce tissue damage following exercise DOMS. However, chemical moist heat only lasts for 2 hours compared to the 8 hours duration of chemical dry heat packs. The purpose of this study was to compare the beneficial effect of dry heat versus moist heat on 100 young subjects after exercise induce DOMS. METHODS: One hundred subjects exercised for 15 minutes accomplishing squats. Before and for 3 days after, strength, muscle soreness, tissue resistance, and the force to passively move the knee were recorded. Heat and moist heat were applied in different groups either immediately after exercise or 24 hours later. RESULTS: The research results of this study showed that immediate application of heat, either dry (8 hours application) or moist (2 hours application), had a similar preservation of quadriceps muscle strength and muscle activity. Results also revealed that the greatest pain reduction was shown after immediate application of moist heat. Never the less, immediate application of dry heat had a similar effect but to a lesser extent. CONCLUSION: It should be noted that moist heat had not only similar benefits of dry heat but in some cases enhanced benefits, and with only 25% of the time of application of the dry heat. (12/2013) (link)
  • Lee H, Petrofsky J S, Daher N, Berk L, Laymon M, & Khowailed I A. (2013). Anterior cruciate ligament elasticity and force for flexion during the menstrual cycle. Medical Science Monitor, 19, 1080-1088. Background: A high occurrence of knee injuries have been observed in women during the menstrual cycle (MC). As a result, numerous studies have been conducted regarding knee ligament elasticity during the MC. Some researchers believe that since estrogen receptor beta exists in ligaments and tendons in the knee, estrogen may modulate towards a state of laxity. However, increased tissue temperature also observed during the MC can predispose ligament and tendon laxness. Therefore, the purpose of this study was to assess in women the relationship between Estradiol (E2) serum concentrations and tissue temperature during the MC and their combined effect on knee laxity. Material/Methods: Ten non-athletic young healthy females, 18 to 30 years of age participated in the study. E2 serum concentrations, anterior cruciate ligament (ACL) elasticity, and force to flex the knee (FFK), knee flexion-extension hysteresis (KFEH) were assessed both at ambient temperature (22 degrees C) and after 38 degrees C warming. Testing was performed multiple times during the participant's MC, for one full MC. Results: ACL elasticity was significantly higher (P<0.01) and FFK and KFEH were significantly lower (p<0.05) during ovulation when E2 levels were highest. ACL elasticity was still higher during ovulation after warming to 38 degrees C. But, the effects of MC on FFK and KFEH were reduced by tissue warming. Conclusions: ACL elasticity, FFK, and KFEH was affected not only by E2 but also tissue temperature. However, E2 had more impact on ACL elasticity while tissue temperature had more impact on FFK and KFEH at 38 degrees C warming. (11/2013)
  • Petrofsky J S, Alshammari F, Bains G S, Khowailed I A, Lee H, . . . Berk L. (2013). What is more damaging to vascular endothelial function: Diabetes, age, high BMI, or all of the above?. Medical Science Monitor, 19, 257-263. Background: It is well established that there is a reduction in the skin blood flow (SBF) in response to heat with age and diabetes. While it is known that high BMI creates a stress on the cardiovascular system and increases the risk of all cause of morbidity and mortality, little is known of the effect of high BMI on SBF response to heat. Since diabetes is associated with age and a higher BMI, the interrelationship between age, BMI and SBF needs to be investigated to better understand the contribution diabetes alone has to endothelial impairment. Material/Methods: This study examined the SBF to heat in young and old people with low and high BMI and people with diabetes with high BMI to determine the contribution these variables have on SBF. Subjects were ten young and older people with BMI <20 and ten young and older people with BMI >20 and ten subjects with diabetes with BMI >20. The SBF response, above the quadriceps, was determined during a 6 minutes exposure to heat at 44 degrees C. Results: Even in young people, SBF after the stress of heat exposure was reduced in subjects with a high BMI. The effect of BMI was greatest in young people and lowest in older people and people with diabetes; in people with diabetes, BMI was a more significant variable than diabetes in causing impairment of blood flow to heat. BMI, for example, was responsible for 49% of the reduction in blood flow after stress heat exposure (R=-0.7) while ageing only accounted for 16% of the blood flow reduction (R=-0.397). Conclusions: These results would suggest the importance of keeping BMI low not only in people with diabetes to minimize further circulatory vascular damage, but also in young people to diminish long term circulatory vascular compromise. (04/2013) (link)
  • Berk L S, Pawar P, Alphonso C, Rekapalli N, Arora R, & Cavalcanti P. (2013). Humor associated mirthful laughter enhances brain EEG power spectral density gamma wave band activity (31-40Hz). Society for Neuroscience Abstract Viewer and Itinerary Planner, 43, . (2013)
  • Petrofsky J S, Berk L, Alshammari F, Lee H, Hamdan A, . . . Al-Nakhli H. (2012). The interrelationship between air temperature and humidity as applied locally to the skin: the resultant response on skin temperature and blood flow with age differences. Med Sci Monit, 18(4), CR201-8. BACKGROUND: Most studies of the skin and how it responds to local heat have been conducted with either water, thermodes, or dry heat packs. Very little has been accomplished to look at the interaction between air humidity and temperature on skin temperature and blood flow. With variable air temperatures and humidity's around the world, this, in many ways, is a more realistic assessment of environmental impact than previous water bath studies. MATERIAL/METHODS: Eight young and 8 older subjects were examined in an extensive series of experiments where on different days, air temperature was 38, 40, or 42 degrees C. and at each temperature, humidity was either 0%, 25%, 50%, 75%, or 100% humidity. Over a 20 minute period of exposure, the response of the skin in terms of its temperature and blood flow was assessed. RESULTS: For both younger and older subjects, for air temperatures of 38 and 40 degrees C., the humidity of the air had no effect on the blood flow response of the skin, while skin temperature at the highest humidity was elevated slightly. However, for air temperatures of 42 degrees C., at 100% humidity, there was a significant elevation in skin blood flow and skin temperature above the other four air humidity's (p<0.05). In older subjects, the blood flow response was less and the skin temperature was much higher than younger individuals for air at 42 degrees C. and 100% humidity (p<0.05). CONCLUSIONS: Thus, in older subjects, warm humid air caused a greater rise in skin temperature with less protective effect of blood flow to protect the skin from overheating than is found in younger subjects. (04/2012)
  • Tanyi R A, Berk L S, Lee J W, Boyd K, & Arechiga A. (2011). THE EFFECTS OF A PSYCHONEUROIMMUNOLOGY (PNI) BASED LIFESTYLE INTERVENTION IN MODIFYING THE PROGRESSION OF DEPRESSION IN CLINICALLY DEPRESSED ADULTS. International Journal of Psychiatry in Medicine, 42(2), 151-166. Objective: Uncontrolled stress can lead to poorly controlled upsurges of cortisol and deregulation of the hypothalamus pituitary-adrenal axis (HPA), thereby leading to major depression. Psychoneuroimmunology (PNI) is the area of medicine dealing with the bidirectional pathways connecting the influences of brain, neuroendocrine, and immune system. Individual PNI-based lifestyle interventions such as humor and guided imagery have been shown to modulate the stress response. However, researchers have not examined the composite effect of a PNI-based lifestyle intervention among clinically depressed adults. Method: This randomized interventional study examined the composite effect(s) of a PNI-based lifestyle intervention: progressive muscle relaxation, spiritual guided imagery, and humor as an adjunct therapy to modifying the progression of depression. Forty-one participants recruited from doctors' offices in San Bernardino and Riverside counties in Southern California, were randomized into two groups: treatment (N = 20) and control (N = 21). For a period of three weeks, participants in the treatment group listened to a 12-minute progressive muscle relaxation and spiritual guided imagery CD daily and watched 10 minutes of humorous DVDs. Participants in both groups were also receiving cognitive behavioral therapy and pharmacotherapy. Results: Depression, spirituality, humor, and stress were assessed at baseline and week 3. Depression significantly decreased from severe to mild from baseline to week 3 in the treatment group. Spirituality significantly increased in the treatment group but remained unchanged in the controls. Conclusions: These findings offer depressed patients alternative approaches to preventing complications and managing their illness in the context of whole-person lifestyle optimization and integration of mind-body-spirit. (Int'l. J. Psychiatry in Medicine 201142:151-166) (2011) (link)
  • Jerrold Petrofsky, Jennifer Batt,  Lee Berk Carol Schweichler, Daisuke Arai, Chelsea Conas, Jennifer Newell, Kelly Case, Krysten Keener, Gurinder Bains. The effect of an exercise and diet program on fitness, posture, and self-image in women. The Journal of Applied Research. Vol.10, No.1, 2010 (11/2010)
  • Bui C, Petrofsky J, Berk L, Shavlik D, Remigio W, Montgomery S. ACUTE EFFECT OF A SINGLE HIGH-FAT MEAL ON FOREARM BLOOD FLOW, BLOOD PRESSURE AND HEART RATE IN HEALTHY MALE ASIANS AND CAUCASIANS: A PILOT STUDY. The Southeast Asian journal of tropical medicine and public health. 2010;41(2):490-500. (2010)
  • Jerrold S. Petrofsky, Katie McLellan, Michelle Prowse, Gurinder Bains, Lee Berk, and Scott Lee. The Effect of Body Fat, Aging, and Diabetes on Vertical and Shear Pressure in and Under a Waist Belt and Its Effect on Skin Blood Flow. Diabetes Technology & Therapeutics 2010 12:2, 153-160  (2010)
  • PETROFSKY, J. S., LAWSON, D. , BERK, L. and SUH, H. (2010), Enhanced healing of diabetic foot ulcers using local heat and electrical stimulation for 30 min three times per week. Journal of Diabetes, 2: 41-46. doi:10.1111/j.1753-0407.2009.00058.x (2010)
  • Petrofsky JS,  Batt J, Berk L, Collins K,  Yang T,  LeMoine M,  Bains G,  Gunda S, Raju C, Vanarasa D, Kim Y, Beard C, Broussard K, Christensen J,  Ellstrom C, George G, Holland M, Vallabhaneni P, Brown J.  (2009) The effect of an aerobic dance and diet program on cardiovascular fitness, body composition, and weight loss in women.   J Appl Res Clin Exp Ther   8;179-188 (07/2009 - 06/2010)
  • 1.      Sirichotirtina, M, Petrosky, JS, Berk, L 2009  Development of a method for assessing strength in extensor digitorum brevis   J Inves. Med 57;167 (07/2009 - 06/2010)
  • Petrofsky JS, Bains, G., Chinna, R., Lohman, E., Berk, L., Prowse, M., Gunda, S.,   Madani, P, Batt, J  (2009)  The effect of the moisture content of a local heat source on the blood flow response of the skin  Arch Dermatol Res. Sep;301(8):581-5. (07/2009 - 06/2010)
  • Acute effect of a single high-fat meal on forearm blood flow, blood pressure and Heart rate in healthy male Asians and Caucasians: a pilot study Chumjit Bui1, Jerrold Petrofsky2, Lee Berk1,2,3, David Shavlik4, Wilton Remigio2 and Susanne Montgomery1. 1Department of Health Promotion and Education, School of Public Health; 2Department of Physical Therapy, School of Allied Health Professions; 3Department of Pathology and Human Anatomy, School of Medicine; 4Department of Epidemiology and Biostatistics, School of Public Health, Loma Linda University, Loma Linda, CA, USA SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH.  Vol 41 No. 2, pg 1-11, March, 2010. (07/2009 - 06/2010)
  • The Effect of Body Fat, Aging, and in and Under a Waist Belt and Its Effect     on Skin Blood Flow in Diabetes on Vertical and Shear Pressure Jerrold S. Petrofsky, Ph.D., J.D., Katie McLellan, Ph.D., Michelle Prowse, M.S., P.T., Gurinder Bains, M.D., Lee Berk, Dr.P.H., M.P.H., C.L.S., and Scott Lee, M.D.   DIABETES TECHNOLOGY & THERAPEUTICS, Volume 12, Number 2,  2010, Pgs 153-160. (07/2009 - 06/2010)
  • Autonomic Stress and Balance- the Impact of Age and Diabetes Accepted for publication in Diabetes Technology and Therapeutics - Manuscript ID DIA-2009-0125.R1.  Feb 3, 2010 (07/2009 - 06/2010)
  • Petrofsky JS, Bains, G., Chinna, R., Lohman, E., Berk, L., Prowse, M., Gunda, S.,   Madani, P, Batt, J  (2009)  The effect of the moisture content of a local heat source on the blood flow response of the skin  Arch Dermatol Res. Sep;301(8):581-5. (2008 - 2009)
  • Stanley A. Tan, Linda G. Tan, Sharon T. Lukman, Lee S. Berk. Humor, as an adjunct therapy in cardiac rehabilitation, attenuates catecholamines and myocardial infarction recurrence. Adv Mind Body Med. 2007 Winter; 22(3-4): 8–12. Background: Catecholamines, especially epinephrine, are implicated in causing arrhythmias, hypertension, and recurrence of myocardial infarction (MI). Diminishing or blocking the effect of catecholamines is useful in cardiac rehabilitation. We have shown previously that a single one-hour episode of mirthful laughter attenuates epinephrine production. Design: We hypothesized that daily participation in mirthful laughter would diminish catecholamine production and improve cardiac rehabilitation. Methods: Forty-eight diabetic patients who had recent MI were randomly divided into two matched groups, and followed for one year in their cardiac rehabilitation programs. The experimental laughter group was asked to view self-selected humor for 30 minutes daily as an adjunct to their standard cardiac therapy. Blood pressure, urinary and plasma epinephrine and norepinephrine levels, and 24-hour Holter recordings were monitored monthly in both experimental and control groups. Results: The patients in the laughter group had fewer episodes of arrhythmias, lower blood pressure, lower urinary and plasma epinephrine and norepinephrine levels, less use of nitroglycerin for angina and a markedly lower incidence of recurrent MI (2/24, 8.3%) than did the control group (10/24, 42%) Conclusion: Laughter attenuates catecholamines and MI recurrence, and thus can be an effective adjunct in post-MI care. (2007) (link)
  • B Bittman, L Berk, M Shannon, M Sharaf, J Westengard, K Guegler, D Ruff. "Recreational music-making modulates the human stress response: A preliminary individualized gene expression strategy.." Med Sci Monit 11.2 (2005): BR31-BR40. , 2005; 11(2): BR31-40. (01/2005)
  • Romano, Berk, Finneran, Kelly, Feng, Carder and Melka. "Anthropogenic sound and marine mammal health: measures of the nervous and immune systems before and after intense sound exposure." Canadian Journal of Fisheries and Aquatic Sciences . (2005): -. (01/2005)
  • Zapater P, Westengard J, Peralta C, Soriano G, Pappas J, Frances R, Munoz C, Runyon BA.. "Nitric oxide in ascetic fluid is an independent predictor of the development of renal impairment in patients with cirrhosis and spontaneous bacterial peritonitis.." 16.6 (2004): 571-577. (01/2004)

Books and Chapters

  • Petrofsky JS and Berk, L. Skin Moisture and Heat Transfer. Springer, Inc. Germany 2011. Art and Science of Moisturizers. (2011 - Present)
  • Berk, L.S. Mind, Body, and Spirit: Exploring the Mind, Body, Spirit Connection through Research on Mirthful Laughter. In Book: Spirituality, Health, and Wholeness: An Introductory Guide for Healthcare Professionals. Publication Nov. 1, 2004.  The Haworth Press. (Requested Chapter by invitation Dr. Henry Lamberton, Associate Dean, School of Medicine, Loma Linda University and editor). (11/2004 - Present)
  • Berk, L.S., S.A. Tan, G. Reiss, and W.C. Eby.  Beta-endorphin response differences to graded exercise between athletes and non-athletes.  In: Exercise Physiology:  Current Selected Research, C.O. Dotson and J.H. Humphrey (Eds.) New York: AMS Press, Inc., 1990, pp. 30-36. (1990 - Present)
  • Berk, L.S., S.A. Tan, D.C. Nieman, and W.C. Eby.  Stress from maximal exercise modifies T-helper and T-suppressor lymphocyte subpopulations and their ratio in man.  In: Exercise Physiology:  Current Selected Research, C.O. Dotson and J.H. Humphrey (Eds.).  New York: AMS Press, Inc., 1988, pp. 1-11. (1990 - Present)

Book Review - Scholarly Journals--Published

  • The effect of a 1 hour aerobic run at 70-80% Max HR on CTx and P1NP biomarkers for bone turnover in physically trained and untrained premenopausal women M.A. Prowse * L.S. Berk * N.S. Daher * J.S. Petrofsky * S. Tonstad * S. Mohan * B. Haddock * L. Wilkin M.A Prowse * L.S. Berk * N. S. Daher * J.S. Petrofsky Schools of Allied Health Professions and Medicine, Loma Linda University, Anderson Street, Loma Linda, CA 92350, USA (07/2009 - 06/2010)

Scholarly Journals--Accepted

  • Petrofsky, JS, Bains, G., Prowse, M., Gunda, S.,  Berk, L.,  Chinna, R., Ethiraju, G., Vanarasa, D., Madani, P  (2009)  Does Skin Moisture Influence The Blood Flow Response To Local Heat?  A reevaluation of the Pennes Model.  J Med Eng Technol. 2009 May 29:1-6. [Epub ahead of print] (2008 - 2009)
  • Petrofsky, JS, Bains, G., Prowse, M., Gunda, S.,  Berk, L.,  Chinna, R., Ethiraju, G., Vanarasa, D., Madani, P  (2009)  Dry Heat, Moist Heat, and Body Fat: are heating modalities really effective in people who are overweight?  J Med Eng Technol. J Med Eng Technol. 2009;33(5):361-9 (2008 - 2009)
  • Petrofsky JS,  Batt J, Berk L, Collins K,  Yang T,  LeMoine M,  Bains G,  Gunda S, Raju C, Vanarasa D, Kim Y, Beard C, Broussard K, Christensen J,  Ellstrom C, George G, Holland M, Vallabhaneni P, Brown J.  (2009) The effect of an aerobic dance and diet program on cardiovascular fitness, body composition, and weight loss in women.   J Appl Res Clin Exp Ther   8;179-188 (2008 - 2009)
  • Sirichotirtina, M, Petrosky, JS, Berk, L 2008  Development of a method for assessing strength in extensor digitorum brevis   J Inves. Med 57;167 (2008 - 2009)
  • Stanley A Tan, Linda G Tan, Sharon T Lukman, Lee S Berk. Humor-associated mirthful laughter, as an adjunct therapy in cardiac rehabilitation, attenuates catecholamines and myocardial infarction recurrence.  Adv Mind Body Med Winter 2007/2008 Vol. 22 No.3/4 8-12. (2007 - 2009)
  • Berk, L.S. The impact of recreational music-making for long-term care workers. Adv Mind Body Med. 2003 Fall-Winter;19(3-4):16.  PMID: 14686267 [PubMed - indexed for MEDLINE] (2002 - 2004)
  • Tanner, M.A., Berk, L.S., Felten, D.L., Blidy, A.D., Somaya, B.L., and Ruff, D.W., Substantial Changes in Gene Expression Level Due to the Storage Temperature and Storage Duration of Human Whole Blood. Clin. Lab. Haem. 24,337-341, 2002. (2001 - 2003)
  • Barry B. Bittman, Berk, L.S., David L. Felten, James Westengard, O. Carl Simonton, James Pappas, and Melissa Ninehouser. Composite Effects of Group Drumming Music Therapy on Modulation of Neuroendocrine-Immune Parameters in Normal Subjects, J. Alternative Therapies in Health and Medicine, Vol. 7, No. 1, 2001, p38-47. (2000 - 2002)
  • Berk, L.S., David L. Felten, Stanley A. Tan, Barry B. Bittman, and James Westengard, MODULATION OF NEUROIMMUNE PARAMETERES DURING THE EUSTRESS OF HUMOR ASSOCIATED MIRTHFUL LAUGHTER. J. Alternative Therapies in Health and Medicine, Vol. 7, No. 2, 2001, p62-76 (2000 - 2002)
  • Berk, L.S., D.C. Nieman, W.S. Youngberg, K. Arabatzis, M. Simpson‑Westerberg, J.E. Lee, S.A. Tan, and W.C. Eby.  The effect of long endurance running on natural killer cells in marathoners.  Med. Sci. Sports Exer.  20:207‑212, 1990. (1989 - 1991)
  • Berk, L.S., Tan, S.A., Fry, W.F., Napier, B.J. et al.  Neuroendocrine and Stress Hormone Changes During Mirthful Laughter.  The Amer. J. Med. Sci. 298, No. 6, 390‑396, 1989. (1988 - 1990)