Lactate Thresholds and the Simulation of Human Energy Metabolism: Contributions by the Cologne Sports Medicine Group in the 1970s and 1980s.

Today, researchers, practitioners, and physicians measure the concentration of lactate during a graded exercise test to determine thresholds related to the maximal lactate steady state (maxLass) as a sensitive measure of endurance capacity. In the 1970s and 1980s, a group of Cologne-based researchers around Wildor Hollmann, Alois Mader, and Hermann Heck developed the methodology for systematic lactate testing and introduced a 4 mmol.L-1 lactate threshold. Later, they also developed the concept of the maxLass, and Mader designed a sophisticated mathematical model of human energy metabolism during exercise. Mader`s model simulates metabolic responses to exercise based on individual variables such as maximum oxygen uptake ( V ˙ O2max) and the maximal rate of lactate formation (νLa.max). Mader's model predicts that the νLa.max reduces the power at the anaerobic threshold and endurance performance but that a high νLa.max is required for events with high power outputs in elite athletes. Mader's model also assumed before the millennium that the rate of fat oxidation is explained by the difference between glycolytic pyruvate synthesis and the actual rate of pyruvate oxidation which is consistent with current opinion. Mader's model also simulated the V ˙ O2max slow component in the mid-1980s. Unfortunately, several landmark studies by the Cologne group were only published in German, and as a result, contributions by the Cologne group are under-appreciated in the English-speaking world. This narrative review aims to introduce key contributions of the Cologne group to human metabolism research especially for readers who do not speak German.

Cancer treatment regimens and their impact on the patient-reported outcome measures health-related quality of life and perceived cognitive function.

BACKGROUND AND PURPOSE: Breast cancer can be a significant challenge for those affected. Knowledge of physical function, social-emotional challenges, and perceived cognitive function based on the cancer treatment regimens may help to inform adequate support. METHODS: For this prospective observational pilot study, we collected data of seventy-nine women (mean age 54.6 ± 9.5 years) before (T0) and after (T1) initial breast cancer treatment. Functional Assessment of Cancer Therapy-Breast (FACT-B) and Functional Assessment of Cancer Therapy-Cognitive-Function (FACT-Cog) were used to collect data of four treatment subgroups: SCR = Surgery + Chemotherapy + Radiation Therapy; SC = Surgery + Chemotherapy; SR = Surgery + Radiation Therapy; S = Surgery. A mixed ANOVA and posthoc analysis (Tukey, Games-Howell) were used to detect interactions (group by time) and the main effect. A repeated-measures ANOVA displayed individual group differences (time). RESULTS: Significant interaction showed more deterioration was experienced with SC and SCR than SR and S for FACT-B (p < 0.01) and FACT-Cog (p < 0.001). The longitudinal comparison between T0 and T1 indicated a significant group main effect on all subscales (p < 0.001) except for Emotional Well-Being. Significant reductions (p < 0.05) in FACT-B, (- 19%); FACT-Cog, (- 21%) with most pronounced effect in Physical Well-Being (- 30%), Functional Well-Being (- 20%), Breast Cancer Subscale (- 20%), Perceived Cognitive Impairments (- 18%) and Impact of Cognitive Impairments on Quality of Life (- 39%) were detected for SCR. CONCLUSION: Our study showed that the extent of change in health-related quality of life (HRQoL) and perceived cognitive function (PCF) depends on the treatment regimen. Multidisciplinary support initiated early in breast cancer therapy is needed, especially for women undergoing combined cancer treatment. Routine assessment of patient-reported outcomes (PROs) in oncology practice may increase the transparency of patients' perceived circumstances, leading to personalized and optimized acute and survivorship care.

Routine cancer treatments and their impact on physical function, symptoms of cancer-related fatigue, anxiety, and depression.

BACKGROUND AND PURPOSE: Breast cancer can be a major challenge for affected women. Knowledge of the physical function, symptoms of cancer-related fatigue, anxiety, and depression based on the cancer treatment may help to guide adequate support. METHODS: For this prospective observational study, we collected data from seventy-nine women with a mean age 54.6 ± 9.5 years prior to the onset of breast cancer treatment (T0) and after (T1/T2). Handgrip strength test (HGS), six-minute walk test (6MWT), the phase angle (PhA), the hospital anxiety and depression scale (HADS), and functional assessment of chronic illness therapy-fatigue (FACIT-F) were used to collect data from four treatment subgroups SC, surgery + chemotherapy; SCR, surgery + chemotherapy + radiation therapy; SR, surgery + radiation therapy; and S, surgery. RESULTS: A mixed ANOVA revealed a significant interaction between time and group for PhA, F = 8.55, p < 0.01; HGS, F = 3.59, p < 0.01; 6MWT, F = 4.47, p < 0.01; and FACIT-F, F = 2.77, p < 0.05 with most pronounced deterioration seen in group SCR (PhA 4.8°; HGS 27.5 kg, 6MWT 453.4 m, FACIT-F 33.8 points). HADS data displayed moderate anxiety and depression predominantly after treatment. CONCLUSION: Our study showed that the extent of change in physical function, symptoms of fatigue, anxiety, and depression depends on the treatment conditions. The potentially higher risk of impaired function due to the prevalence of values below a critical threshold requires early initiated multidisciplinary support.

Routine Cancer Treatment Regimens and Its Impact on Fine Motor Dexterity in Breast Cancer.

INTRODUCTION: Breast cancer can be a major challenge for those affected. Knowledge of changes in fine motor dexterity in affected women due to routine cancer therapies can help guide effective support. METHODS: For this prospective observational study, we collected data of 79 women with a mean age 54.6 ± 9.5 years prior to, after breast cancer therapy (T1), and at 3-month follow-up. The fine motor dexterity was assessed for 4 treatment subgroups: SC = Surgery + Chemotherapy, SCR = Surgery + Chemotherapy + Radiotherapy Therapy, SR = Surgery + Radiotherapy, and S = Surgery. RESULTS: Over time, women with breast cancer showed significant decreases in fine motor dexterity across all treatment groups (p < 0.001). The strongest negative effect was seen in the treatment groups receiving additional chemotherapy. SCR group showed pronounced limitations for dominant hand (DH) -12%; non-dominant hand (NDH) -15%; both hands (BH) -17%; assembly (ASSY) -11% at T1. Significant interaction was noticeable in DH (F = 5.59, p < 0.001), NDH (F = 6.61, p < 0.001), BH (F = 13.11 p < 0.001), and ASSY (F = 5.84 p < 0.001). DISCUSSION/CONCLUSION: Our study showed that the extent of change in fine motor dexterity depends on the treatment regimen. The detection of unmet care needs could help to personalize and optimize clinical and survivorship care. Based on our findings, multidisciplinary support initiated early in breast cancer therapy is required.

The effectiveness of blood-flow restricted resistance training in the musculoskeletal rehabilitation of patients with lower limb disorders: A systematic review and meta-analysis.

OBJECTIVE: This meta-analysis aimed to evaluate the effectiveness of low-load Resistance Training (RT) with or without Blood Flow Restriction (BFR) compared with conventional RT on muscle strength in open and closed kinetic chains, muscle volume and pain in individuals with orthopaedic impairments. DATA SOURCES: Searches were conducted in the PubMed, Web of Science, Scopus and Cochrane databases, including the reference lists of randomised controlled trials (RCT's) up to January 2021. Review method: An independent reviewer extracted study characteristics, orthopaedic indications, exercise data and outcome measures. The primary outcome was muscle strength of the lower limb. Secondary outcomes were muscle volume and pain. Study quality and reporting was assessed using the TESTEX scale. RESULTS: A total of 10 RCTs with 386 subjects (39.2 ± 17.1 years) were included in the analysis to compare low-load RT with BFR and high or low-load RT without BFR. The meta-analysis showed no significant superior effects of low-load resistance training with BFR regarding leg muscle strength in open and closed kinetic chains, muscle volume or pain compared with high or low-load RT without BFR in subjects with lower limb impairments. CONCLUSION: Low-load RT with BFR leads to changes in muscle strength, muscle volume and pain in musculoskeletal rehabilitation that are comparable to conventional RT. This appears to be independent of strength testing in open or closed kinetic chains.

Bioelectrical Impedance Vector Pattern and Biomarkers of Physical Functioning of Prostate Cancer Survivors in Rehabilitation.

BACKGROUND: Knowledge of clinically established factors of physical function such as body composition, bioelectrical phase angle (PhA) and handgrip strength (HGS) with mortality predictive and health-related relevance is limited in prostate cancer survivors (PCS). Therefore, the aim of this study was to characterise and compare body composition data of PCS with extensive reference data as well as to analyse PhA and HGS and the prevalence of critical prognostic values at an early stage of cancer survivorship. METHODS: One hundred and forty-eight PCS were examined at the start (T1) and end (T2) of a 3-week hospitalised urooncological rehabilitation, which began median 28 days after acute cancer therapy. Examinations included a bioimpedance analysis and HGS test. Comparison of body composition between PCS and reference data was performed using bioimpedance vector analysis (BIVA). RESULTS: BIVA of the whole PCS group showed abnormal physiology with a cachectic state and a state of overhydration/oedema, without significant changes between T1 and T2. The age- and BMI-stratified subgroup analysis showed that PCS aged 60 years and older had this abnormal pattern compared to the reference population. HGS (T1: 38.7 ± 8.9 vs T2: 40.8 ± 9.4, kg), but not PhA (T1/T2: 5.2 ± 0.7, °), changed significantly between T1 and T2. Values below a critical threshold reflecting a potentially higher risk of mortality and impaired function were found for PhA in 20% (T1) and 22% (T2) of PCS and in 41% (T1) and 29% (T2) for HGS. CONCLUSIONS: BIVA pattern and the prevalence of critically low HGS and PhA values illustrate the necessity for intensive continuation of rehabilitation and survivorship care especially in these 'at risk' cases. The routine assessment of body composition, PhA and HGS offer the opportunity to conduct a risk stratification for PCS and could help personalising and optimising treatment in rehabilitation and ongoing survivorship care.

Adaption of Maximal Glycolysis Rate after Resistance Exercise with Different Volume Load.

The aim of this study was to investigate the effect of six-weeks of resistance training with different volume load on the maximum glycolysis rate. 24 male strength-trained volunteers were assigned in a high volume low load (50% of their 1RM with 5 sets and reps up to muscle failure) and a low volume high load (70% of their 1RM with 5 sets of ten reps) resistance exercise group. The resistance training performed 3 days per week over 6 weeks. The maximum glycolysis rate was determined using isokinetic force testing before and after the intervention. There was a significant increase in glycolysis rate over the training period across all subjects (p=0.032). High volume low load exercise increased significantly from 0.271±0.067 mmol·l -1 ·s -1 to 0.298±0.067 mmol·l -1 ·s -1 (p=0.022) and low volume high load exercise showed no significant changes from 0.249±0.122 mmol·l -1 ·s -1 to 0.291±0.089 mmol·l -1 ·s -1 (p=0.233). No significant effect on glycolysis rate was observed between the training groups (p=0.650). Resistance training increases glycolysis rate regardless of volume load.

Effects of six-week sprint interval or endurance training on calculated power in maximal lactate steady state.

The purpose of the study was to evaluate and compare the influence of sprint interval training (SIT) and endurance training (ET) on calculated power in maximal lactate steady state (PMLSS) (influenced by the maximal lactate production rate (⩒Lamax) and maximal oxygen uptake (⩒O2max)). Thirty participants were randomly assigned to the a) SIT, b) ET, or c) control group (n = 10 each). Each session consisted of four to six repetitions of 30 s all-out effort Wingate anaerobic tests (SIT) or 60 min cycling at 1.5 to 2.5 mmol∙L-1 blood lactate (analysed every 10 min). Both groups performed training on three days per week, over a period of six weeks. To measure ⩒Lamax and ⩒O2max, and to calculate PMLSS, sprint and ramp tests were performed at baseline and after two, four and six weeks of intervention. While SIT resulted in a significant reduction of ⩒Lamax (-0.08 ± 0.05 mmol∙L-1∙s-1, p=0.003) after two weeks and remained subsequently stable, ⩒O2max (+2.6 ± 2.4 ml∙min-1∙kg-1, p = 0.044) and PMLSS (+25 ± 14 W, p=0.002) increased, but not before six weeks of SIT. After two weeks of ET, ⩒Lamax remained unchanged, but ⩒O2max increased by increased by +2.9 ± 2.4 ml∙min-1∙kg-1, p=0.03, and after six weeks by 5.6 ± 3.5 ml∙min-1∙kg-1. The increase of PMLSS was significant after four weeks of ET (+16 ± 14 W, p=0.036) and increased to +32 ± 17 W after six weeks. Comparison of SIT and ET revealed no significant differences for ⩒Lamax, ⩒O2max or PMLSS after six weeks. The control group remained stable in all parameters. In both exercising groups there was a significant improvement of the calculated PMLSS due to different influences of ⩒Lamax and ⩒O2max.

Reproducibility of Blood Lactate Concentration Rate under Isokinetic Force Loads.

(1) Background: Maximum isokinetic force loads show strongly increased post-load lactate concentrations and an increase in the maximum blood lactate concentration rate ( V ˙ Lamax), depending on load duration. The reproducibility of V ˙ Lamax must be known to be able to better assess training-related adjustments of anaerobic performance using isokinetic force tests. (2) Methods: 32 subjects were assigned to two groups and completed two unilateral isokinetic force tests (210° s-1, Range of Motion 90°) within seven days. Group 1 (n = 16; age 24.0 ± 2.8 years, BMI 23.5 ± 2.6 kg m-2, training duration: 4.5 ± 2.4 h week-1) completed eight repetitions and group 2 (n = 16; age 23.7 ± 1.9 years, BMI 24.6 ± 2.4 kg m-2, training duration: 5.5 ± 2.1 h week-1) completed 16 repetitions. To determine V ˙ Lamax, capillary blood (20 µL) was taken before and immediately after loading, and up to the 9th minute post-load. Reproducibility and variability was determined using Pearson and Spearman correlation analyses, and variability were determined using within-subject standard deviation (Sw) and Limits of Agreement (LoA) using Bland Altman plots. (3) Results: The correlation of V ˙ Lamax in group 1 was r = 0.721, and in group 2 r = 0.677. The Sw of V ˙ Lamax was 0.04 mmol L-1 s-1 in both groups. In group 1, V ˙ Lamax showed a systematic bias due to measurement repetition of 0.02 mmol L-1 s-1 in an interval (LoA) of ±0.11 mmol L-1 s-1. In group 2, a systematic bias of -0.008 mmol L-1 s-1 at an interval (LoA) of ±0.11 mmol L-1 s-1 was observed for repeated measurements of V ˙ Lamax. (4) Conclusions: Based on the existing variability, a reliable calculation of V ˙ Lamax seems to be possible with both short and longer isokinetic force loads. Changes in V ˙ Lamax above 0.11 mmol L-1 s-1 due to training can be described as a non-random increase or decrease in V ˙ Lamax.

The influence of body composition on exercise-associated skin temperature changes after resistance training.

Resistance exercise leads to an increase in skin temperature (Tskin) in the area of the exercised muscle. Infrared thermography seems to be applicable to identify these primary used functional muscles with measuring Tskin changes. The aim of the current study was to investigate the influence of body composition on Tskin patterns after resistance exercise. 38 male subjects (19-32 years, BMI 20.4-55.2 kg/m2) participated. Body fat percentage and biceps skinfold thickness were calculated. The subjects were divided into two groups: lean group (LG) with body fat percentage < 25%, obese group (OG) with body fat percentage ≥ 25%. All participants completed three sets with ten repetitions of unilateral biceps curl at 50% of the one repetition maximum. To represent exercise-induced changes of Tskin to rest (Trest), the algebraic difference of each time point to Trest was calculated. The resulting delta values (∆) are as follows: immediately after the first, second, and third set (∆Tset1,∆Tset2,∆Tset3), and at 1,2,3,4,5,6,7,8,9,10,15,20,25,30 min after the third set (∆T1-∆T30). The maximum positive difference to Trest was defined as ∆Tmax, and the time to reach ∆Tmax was defined as Time to ∆Tmax. LG and OG differed significantly at Trest (32.8 ±â€¯0.9 vs. 31.1 ±â€¯1.4 °C), ∆Tmax (1.9 ±â€¯0.4 vs. 0.9 ±â€¯0.8 °C), Time to ∆Tmax (4.5 ±â€¯2.0 vs. 17.6 ±â€¯10.2 min) and at ∆Tset2 to ∆T15 (p < 0.005). Correlations between body composition (BMI, body fat percentage, biceps skinfold thickness) and Trest, ∆Tset2, ∆Tset3, ∆Tmax (-0.47 

Evaluation of the Characteristics of a Workplace Assessment Form to Assess Entrustable Professional Activities (EPAs) in an Undergraduate Surgery Core Clerkship.

OBJECTIVE: Entrustable Professional Activities (EPAs) are explicit, directly observable tasks requiring the demonstration of specific knowledge, skills, and behaviors that learners are expected to perform without direct supervision once they have gained sufficient competence. Undergraduate level implementation of EPAs is relatively new. We examined the characteristics of a workplace assessment form (clinic card) as part of a formative programmatic assessment process of EPAs for a core undergraduate surgery rotation. DESIGN: A clinic card was introduced to assess progression towards EPA achievement in the clerkship curriculum phase. Students completing their core eight (8) week clerkship surgery rotation submitted at least 1 clinic card per week. We compiled assessment scores for the 2015 to 2016 academic year, in which EPAs were introduced, and analyzed relationships between scores and time, EPA, training site, and assessor role. We surveyed preceptors and students, and conducted a focus group with clinical discipline coordinators of all core rotations. SETTING: This study took place at the Faculty of Medicine, Memorial University in St. John's, Newfoundland, Canada. PARTICIPANTS: Third year medical students (n = 79) who completed their core eight (8) week surgery clerkship rotation during the 2015 to 2016 academic year, preceptors, and clinical discipline coordinators participated in this study. RESULTS: EPAs reflecting tasks commonly performed by students were more likely to be assessed. EPAs frequently observed during preceptor-student encounters had higher entrustment ratings. Most EPAs showed increased entrustment scores over time and no significant differences in ratings between teaching sites nor preceptors and residents. Survey and focus group feedback suggest clinic cards fostered direct observation by preceptors and promoted constructive feedback on clinical tasks. A binary rating scale (entrustable/pre-entrustable) was not educationally beneficial. CONCLUSIONS: The findings support the feasibility, utility, catalytic and educational benefits of clinic cards in assessing EPAs in a core surgery rotation in undergraduate medical education.

Comparison of calculated and experimental power in maximal lactate-steady state during cycling.

BACKGROUND: The purpose of this study was the comparison of the calculated (MLSSC) and experimental power (MLSSE) in maximal lactate steady-state (MLSS) during cycling. METHODS: 13 male subjects (24.2 ± 4.76 years, 72.9 ± 6.9 kg, 178.5 ± 5.9 cm, V˙O2max: 60.4 ± 8.6 ml min-1 kg-1, V˙Lamax: 0.9 ± 0.19 mmol l-1 s-1) performed a ramp-test for determining the V˙O2max and a 15 s sprint-test for measuring the maximal glycolytic rate (V˙Lamax). All tests were performed on a Lode-Cycle-Ergometer. V˙O2max and V˙Lamax were used to calculate MLSSC. For the determination of MLSSE several 30 min constant load tests were performed. MLSSE was defined as the highest workload that can be maintained without an increase of blood-lactate-concentration (BLC) of more than 0.05 mmol l-1 min-1 during the last 20 min. Power in following constant-load test was set higher or lower depending on BLC. RESULTS: MLSSE and MLSSC were measured respectively at 217 ± 51 W and 229 ± 47 W, while mean difference was -12 ± 20 W. Orthogonal regression was calculated with r = 0.92 (p < 0.001). CONCLUSIONS: The difference of 12 W can be explained by the biological variability of V˙O2max and V˙Lamax. The knowledge of both parameters, as well as their individual influence on MLSS, could be important for establishing training recommendations, which could lead to either an improvement in V˙O2max or V˙Lamax by performing high intensity or low intensity exercise training, respectively. Furthermore the validity of V˙Lamax -test should be focused in further studies.

Recommendations for promoting physical activity for children and adolescents in Germany. A consensus statement.

Increasing physical activity and reduction of sedentary behaviour play important roles in health promotion and prevention of lifestyle-related diseases in children and adolescents. However, the question of how much physical activity is useful for which target group is still a matter of debate. International guidelines (World Health Organization; European Association for the Study of Obesity), which are mainly based on expert opinions, recommend 60 min of physical activity every day. Age- and sex-specific features and regional differences are not taken into account. Therefore, expert consensus recommendations for promoting physical activity of children and adolescents in Germany were developed with special respect to national data, but also with respect to aspects of specific target groups, e.g., children with a lower socio-economic status (SES) or with migration background. They propose 90 min/day of physical activity, or at least 12,000 steps daily. Additionally, lifestyle factors, especially restriction of media consumption, were integrated. The recommendations provide orientation for parents and caregivers, for institutions such as schools and kindergartens as well as for communities and stakeholders.

Reliability of the interprofessional collaborator assessment rubric (ICAR) in multi source feedback (MSF) with post-graduate medical residents.

BACKGROUND: Increased attention on collaboration and teamwork competency development in medical education has raised the need for valid and reliable approaches to the assessment of collaboration competencies in post-graduate medical education. The purpose of this study was to evaluate the reliability of a modified Interprofessional Collaborator Assessment Rubric (ICAR) in a multi-source feedback (MSF) process for assessing post-graduate medical residents' collaborator competencies. METHODS: Post-graduate medical residents (n = 16) received ICAR assessments from three different rater groups (physicians, nurses and allied health professionals) over a four-week rotation. Internal consistency, inter-rater reliability, inter-group differences and relationship between rater characteristics and ICAR scores were analyzed using Cronbach's alpha, one-way and two-way repeated measures ANOVA, and logistic regression. RESULTS: Missing data decreased from 13.1% using daily assessments to 8.8% utilizing an MSF process, p = .032. High internal consistency measures were demonstrated for overall ICAR scores (α = .981) and individual assessment domains within the ICAR (α = .881 to .963). There were no significant differences between scores of physician, nurse, and allied health raters on collaborator competencies (F2,5 = 1.225, p = .297, η2 = .016). Rater gender was the only significant factor influencing scores with female raters scoring residents significantly lower than male raters (6.12 v. 6.82; F1,5 = 7.184, p = .008, η 2 = .045). CONCLUSION: The study findings suggest that the use of the modified ICAR in a MSF assessment process could be a feasible and reliable assessment approach to providing formative feedback to post-graduate medical residents on collaborator competencies.

A comparison of face-to-face versus remote assessment of neonatal resuscitation skills.

The neonatal resuscitation skills of 30 third-year medical students were assessed in real time by a face-to-face examiner in the same room as the student, and by a remote examiner located in a separate room using the ANAKIN system. The ANAKIN system combines an instrumented manikin simulator, computer-based assessment and high-bandwidth videoconferencing. The students were assessed while performing a neonatal resuscitation megacode using the ANAKIN system. Students were satisfied with the ANAKIN system as an assessment system and were not intimidated by its use. However, the correlation between the face-to-face and remote examiner's mean total performance assessment scores was 0.27, which was not significant (P=0.14). The results indicated variation between the examiners' performance scores in a number of key technical skill areas. The findings from this study have implications for the use of technology-mediated systems in assessing resuscitation skills. Examiner orientation is critical for individuals using such systems. These persons must be comfortable and confident in using the technology. Interface and design features of the system need to be carefully scrutinized and tested.