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Aging Research at Tufts UniversityFiatarone et al., 1990
Bassey et al., 1992
High-Intensity Strength Training in Nonagenarians
• Effects on Skeletal Muscle• JAMA, 1990
Rationale
• Biologic aging (??)• Disease• Sedentary lifestyle• Nutritional inadequacies• All related to type II fiber atrophy
• Intervention?• Weakness Falls
Aims
To determine• Feasibility• Physiological consequences• High-resistance strength training in the
frail elderly
Participants
• Long term care facility (“nursing home”)• Ambulatory• Not acutely ill• Follow instructions• No unstable disease
Participant Characteristics (Table 1.)
Characteristic Mean±SEM Range
Age (y) 90.2 (1.1) 86-96
F 6
M 4
Length of stay (y) 3.4(0.8) 0.7-8.3
Hx of falls 8
Use of assistive device
7
Chronic dz/person 4.5 (0.6) 2-7
Daily meds/person 4.4 (0.8) 0-9
Measures
• Body composition• Total and regional
• Diet records• 1RM • Safety measures
• Functional mobility
Training
• 8 weeks• Con/Ecc leg extension• 3 x/wk• 3 sets of 8• 6-9 seconds• 1-2 min rest• 80% 1RM
• 2 & 4 weeks of detraining
Results: Participants
• Level of care• Excluded• MI• Fracture• Behavioral• Arthritis
Results: Participants
• 40% signs of under nutrition• FFM higher in men than in women• SSkFs highly related to BF% (r=0.89,
P<.001)• Regional muscle area highly related to
total body FFM (r=.98, P<.0001)
Results: Baseline Muscle Function
• Right leg: 9.0±1.4• Left leg: 8.9±1.7• Corr with FFM
(r=.732; P<.01)• Corr with thigh
muscle area (r=.752, P<.01)
• Dietary intake• Chair stand
2.2±0.5 sec• 6m walk time
22.2±4.6 sec• Both related to
1RM (how?)
Response to Training
• 9 of 10 completed protocol• 98.8% attendance• No CV complications• Minor joint discomfort
Muscle Strength
• 174 ± 31% increase • 8.02±1.0 kg to 20.6 ± 2.4 kg (right)• 7.6±1.3 kg to 19.3±2.2 kg (left)• No plateau• Same among men and women
Clinical Outcomes
• No change in gait speed• Tandem gait improvements (N=5)• 2 no longer needed canes• 1 of 3 could rise from chair w/o arms
Discussion
• Dramatic increases in strength• 61-374% (!!!)
• Reversal of age-related weakness• Principle of specificity
• Previous research• Remarkable findings given potential limitations of
population• Familiarization??• Hypertrophy or neural improvements?• Well tolerated• Limitations• Safety of training versus not training (ie, falls)
Leg extensor power and functional performance in very old men and women
• Bassey et al., 1992• Clinical Science
Rationale & Aim
• Power is the basis for daily activities• Short time requirement• Importance of leg extensors in ADLs
….To what extent power output …..predicted performance in older people
Participants
• Same location as in Fiatarone et al., 1990• N=26• Familiar with procedures (presumably
study staff)• Ambulatory but often used wheelchairs• Meds, falls, chronic conditions• Some cognitive impairment
Participants
Age (yrs)
Wt (kg) Ht (m) # of CCs*
# of Meds
Men (N=13)
88 (1.6) 64.7 (2.7)
1.58 (0.03)
64 5.2 (2.4)
Women (N=13)
85 (1.5) 54.7 (2.8)
1.50 (0.03)
55 5.2 (2.1)
* Diabetes, hypertension, heart disease, Parkinson’s, neurological disease, arthritis, syncope, musculo-skeletal defect, cancer, other
Measures
• Leg extensor power (<1 sec)• Right, left, both, best
•Chair rising (1 time)• Stair climbing (4 steps)•Walking (6 m)
Results
• All completed • Leg extensor power• Walking speed
• Chair rise• N=1 (man)
• Stair climb• N=3 (women)
Results
• Good reliability (test-retest)• Neurological & musculo-skeletal disease• Gender or sex??• Use of aids (ie, cane, walker, arms to rise)• 1.1 vs 1.9 W/kg• 0.86 vs 1.87 W/kg
Discussion
• Feasibility• Normative data for power?• Power vs strength• Differences between men and women• Performance of participants• Threshold values• Walking (is this about balance?)• All
• Cause-effect?
Summary
•Muscle strength•Muscle power• Feasibility•Approach to training?• Specificity!!