CIRCULATORY RESPONSES TO WEIGHT-LIFTING, WALKING, AND STAIR CLIMBING IN OLDER MALES

OBJECTIVES: To compare the heart rate and intra-arterial blood pressur e responses during weight lifting, horizontal and uphill walking, and stair climbing in older male subjects. DESIGN: We used intra-brachial artery catheterization to compare the arterial blood pressure (ABP) an d heart rate (HR) responses during 10 repetitions (similar to 40 s) of single-arm curl (SAG) and single-arm overhead military press (SAMP) ( 70% of the one repetition maximum - 1RM); 12 repetitions (similar to 5 0 s) of single- (SLP) and double-leg press (DLP) weight lifting exerci ses (80% of 1RM); 10 minutes of horizontal treadmill walking (T10) at 2.5 mph holding a 20-pound weight in minutes 4 to 6 (T10(4-6)) and 30 pounds in minutes 8 to 10 (T10(8-10)); 4 minutes of treadmill walking (T4) at 3.0 mph up an 8% incline; and 12 flights (192 steps) of stair climbing (STR) at 60 to 65 steps/minute on a Stairmaster 6000 ergomete r (similar to 3 minutes). SETTING: McMaster University, Hamilton, Onta rio, Can ada. PARTICIPANTS: Seventeen healthy males aged ((X) over bar +/- SE) 64.4 +/- 0.6 years. MEASUREMENTS: Continuous intra-arterial m easurements of systolic, diastolic, and mean arterial pressure and hea rt rate and rate-pressure product. RESULTS: The peak values of HR, ABP and rate-pressure product (HR . BPs/1000;(RPP,10(3))) were not system atically ordered among the various activities. The lowest peak values for all variables were recorded during the initial 4 minutes of horizo ntal treadmill walking. The STR and T4 walking exercises elicited high er HRs (151 +/- 3.2 and 121 +/- 3.4 bpm) than the weight lifting (rang e from 100 +/- 4.8 (SAG) to 113 +/- 3.8 bpm (SAMP)), but the converse was true for diastolic pressure (range from 128 +/- 6.3 (SAG) to 151 /- 4.8 mm Hg (SAMP) versus 101 +/- 2.5 (T4) to 118 +/- 3.4 mm Hg (T10( 8-10)) and mean arterial pressure (range from 145 +/- 4.5 (SAG) to 158 +/- 4.8 mm Hg (SAMP) versus 129 +/- 3.4 in T4 to 148 +/- 3.8 (T10(8-1 0)) and 157 +/- 4.1 mm Hg (STR)). The peak systolic pressure was great est in STR (271 +/- 9.6 mm Hg) followed by SAMP (261 +/- 9.3 mmHg) and T10(8-10) (244 +/- 6.4 mm Hg) and was lowest in SAC (224 +/- 10.5 mm Hg) and T10(4-6) (220 +/- 5.7 mm Hg). The peak RPP descended in sequen ce from STR (41 +/- 1.8), SAMP (29.8 +/- 1.7), T4 (28.1 +/- 1.3), DLP (27.2 +/- 1.3), T10(8-10) (27.1 +/- 1.4), SLP (25.4 +/- 1.7), T10(4-6) (22.7 +/- 1.2) and SAC (22.0 +/- 2.2). CONCLUSION: We concluded that older adults who engage in weight lifting with heavy submaximal loads are exposed to no more peak circulatory stress than that created durin g a few minutes of inclined walking. Moreover, climbing only three to four flights of stairs at a moderate pace (similar to 50-70 s) elicits peak circulatory demands similar to, but at a much more rapid rate of adjustment than, 10 minutes of horizontal walking at 2.5 mph intermit tently carrying a 30-pound weight or 4 minutes of walking up a moderat ely steep slope.