Progressive improvement in glucose tolerance following lower-intensity resistance versus moderate-intensity aerobic training in older women.
BACKGROUND
Few studies have compared long-term moderate-intensity aerobic versus light-resistance training on serial improvements in glucose tolerance in older people.


METHODS
Healthy, inactive older (74 +/- 5 [SD] years) women (N = 20) were randomized into either a high-volume, moderate-intensity aerobic (ATM, n = 12) or a lower-intensity resistance training (RTL, n = 8) group. Both groups exercised under supervision 4 times per week for 45- to 60-min sessions over 9 months. Measurements of plasma glucose, insulin, and free fatty acid (FFA) responses to an oral glucose tolerance test (OGTT) were performed at baseline and at 3, 6, and 9 months 48 hours after the last exercise session.


RESULTS
We observed significant improvements in 2-hour glucose concentrations at 3, 6, and 9 months among women in the RTL(152 +/- 42 vs 134 +/- 33 vs 134 +/- 24 vs 130 +/- 27 mg x dL-1; P < .05), but not the ATM(151 +/- 25 vs 156 +/- 37 vs 152 +/- 40 vs 155 +/- 39 mg x dL-1) group. These improvements were accompanied by an 18% (P < .07) decrease in basal FFA concentrations in the RTLgroup, whereas basal and 30-min FFA concentrations increased (P < .05) after training in the ATMgroup.


CONCLUSIONS
These findings suggest that the net physiological benefits of exercise might have been blunted in the ATMgroup, owing to higher circulating levels of FFA, which might have temporarily interfered with insulin action.
Dipietro
Loretta
L
JB Pierce Laboratory, Yale University, New Haven, CT 06519, USA.
Yeckel
Catherine W
CW
Dziura
James
J
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001786:Blood Glucose / Q000032:analysis*; D015992:Body Mass Index; D003237:Connecticut; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D055070:Resistance Training; D013997:Time Factors
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin