Weight Bearing Exercise in Preventing Frailty in Stage I-IIIA Breast Cancer Survivors

Demonstrate reproducibility of forearm muscle activation and subcutaneous fat measures in a healthy convenience sample/population (N= 10). Standard anthropometric measurements (height, weight, waist, hip and arm circumferences) will be taken at baseline and 8weeks. A total body dual energy X-ray absorptiometry (DXA) scan, with an effective radiation dose of about 0.01 mSv, which is about the same as background radiation in one day according to the American College of Radiology (http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_xray#3), will be used to determine fat mass and fat free mass at these same time-points. Skeletal muscle mass will be determined by using both appendicular lean mass/height2 method and the residuals model from the Health ABC Study.

Skeletal muscle mass will be determined by using both appendicular lean mass/height2 method and the residuals model from the Health ABC Study.

Maximal isometric muscle activation of the forearm flexors by electromyography (EMG) will be assessed by a pair of surface electrodes (plus 1 ground), to minimize participant burden. EMG data will be amplified and recorded by BIOPAC Systems MP35, 4-channel acquisition system and BSL Pro 3.7 software (BIOPAC Systems, Inc. Goleta, CA), during each of 4, 2-second, repetitions on the 100kg hand grip isometric dynamometer, integrated into the BIOPAC system. Sampling rate and acquisition length will be standardized. The I-beam tool will select the initiation of and conclusion of each contraction. Contraction 1 for each participant will be used for exercise familiarization and dropped, contractions 2-4 will be averaged to for maximal isometric muscle activation (mV). Normally, the non-dominant arm would be evaluated, but since this particular population may have functional limitations on either or both sides due to surgery (i.e. lymphectomy or mastectomy), both arms will be measured.

A standard submaximal test of strength, 8-12 repetition maximum (RM) will used to evaluate strength and maintain loads in the lower body, which has been safe and effective in previous studies. Strength by hand grip dynamometer will also be measured at baseline and 8wks post-training.

Insulin, insulin resistance (homeostasis model of insulin resistance, HOMA-IR), growth factors and pro-inflammatory cytokines will be evaluated. Assays will be performed in duplicate for insulin and in triplicate for glucose, based on prior assay experience, with baseline and 8 wk samples for each individual run within the same assay. An Insulin Radioimmunoassay Kit will be used to quantify fasting insulin levels.Determination of glucose will be performed by colorimetric assay via the glucose oxidase method and spectrophotometer. Past intra- and inter-assay CVs were 5% and 8% for glucose measures respectively. HOMA-IR = insulin0 (uU/ml)*glucose0 (mmol/l)) / 22.5.

Highly sensitive ELISA kits will be used to measure circulating cytokines, such as IL-6 or CRP and growth factors, such as IGF-1 in duplicate. Controls for each assay will be run concurrently on each plate. Each assay will be run with intra and inter assay CVs of <5% and <10% respectively.

DNA extraction from blood buffy coat or whole blood will be performed using the FlexiGene DNA Kit following the protocol for Isolation of DNA from 100-500µl Buffy Coat. Quantitative and qualitative DNA analysis will be performed by the Quant-iT™ PicoGreen® dsDNA Assay Kit and by performing 558bp polymerase chain reaction (PCR) and separation by gel electrophoresis on a 2% agarose gel, stained with ethidium bromide for visualization. Determination of polymorphisms related to body composition, exercise or chronic disease will be performed using TaqMan® Pre-Designed SNP Genotyping Assays with allelic discrimination by the ABI PRISMTM 7700 Sequence Detector. If TaqMan technology is not suitable for a particular polymorphism, then simple multiplex PCR with primers designed by Midland Chemicals will be performed and allelic determination will be conducted by ethidium bromide visualization on agarose gel. Universal PCR thermocycling conditions will be used.