abstract methods results results (cont.)The Big Blue Test (BBT) is a program run by the Diabetes Hands Foundation (DHF) to raise awareness of the importance of physical activity in managing diabetes. During the 2011 BBT, data were collected in one of two ways: 1) individuals doing the BBT entered their results on the web site BigBlueTest.org (in English or Spanish); or 2) at group events (e.g., dance-a-thons and walks), participant results were collected and entered post-event by DHF personnel through the same web site. All participants were required to indicate if they have diabetes, the type of physical activity done (ranging widely from walking to martial arts and yoga), blood glucose readings before and after 14 minutes of exercise, and insulin use. A total of 3,916 people with diabetes completed the BBT (78.8% insulin users).

Although 89.2% of participants experienced a decrease in blood glucose levels as a result of BBT participation, the decrease was significantly greater in insulin users and more of them experienced post-exercise hypoglycemia (p<0.05). Only 0.8% of participants (23 insulin users and 10 non-insulin users) recorded no change in blood glucose levels post-exercise, whereas 391 had increased levels (10.0% of insulin users, 10.3% of non-insulin users). In conclusion, the BBT has demonstrated that participation in 14 minutes of varying types of physical activity effectively lowers blood glucose levels in most individuals.

introduction

references

For most people with any type of diabetes, engaging in physical activity has a blood glucose lowering effect and can assist in diabetes management.1 Hypoglycemia (defined as a blood glucose <65 mg/dL) can also result from exercise participation and is a concern particularly for insulin users with type 1 or type 2 diabetes.2

The Big Blue Test (BBT) is a program run by the Diabetes Hands Foundation to raise awareness of the importance of physical activity in managing diabetes. This past year, in addition to encouraging people with diabetes to experience the effects of varying types of physical activity on their blood glucose levels, the BBT was set up to collect individuals’ results.

Our purpose was to document the glycemic effects of 14 minutes (in honor of World Diabetes Day, on November 14) of any physical activity, along with the incidence of hypoglycemia related to the chosen activity, in both insulin and non-insulin users with diabetes.

• During the 2011 BBT, data were collected in two ways: 1) individuals doing the BBT entered their results on the web site BigBlueTest.org (in English or Spanish); or 2) at group events (e.g., dance-a-thons and walks), participant results were collected and entered post-event by Diabetes Hands Foundation personnel through the same web site.

• All participants were required to indicate their diabetes status, the type of physical activity they chose to do, blood glucose readings obtained through self-monitoring with a blood glucose meter before and after 14 minutes of exercise, and whether or not they use exogenous insulin.

• Since many of the individuals involved in the BBT were native Spanish speakers rather than English speakers, a secondary purpose of the BBT data collection was to examine the effect that cultural differences may have had on physical activity participation outcomes.

• All data were reported as mean±SEM (where appropriate) and analyzed using non-paired t-tests to compare insulin and non-insulin users. Significance was set at p<0.05.

• A total of 3,916 people with diabetes completed the BBT, 78.8% of whom were insulin users (as shown in Table 1).

• The types of physical activities that individuals reported doing varied widely, from walking to martial arts and yoga, meaning that their intensity ranged from low to high.

• English-speaking (ES) participants comprised 83.3% of the total, native Spanish-speakers (SS) 16.7% (Table 2).

1 Colberg SR, Sigal RJ, Fernhall B, Regensteiner JG, Blissmer BJ, Rubin RR, Chasan-Taber L, Albright AL, Braun B; American College of Sports Medicine; American Diabetes Association. Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: joint position statement. Diabetes Care. 2010;33(12):e147-67.

2 Briscoe VJ, Tate DB and Davis SN. Type 1 diabetes: exercise and hypoglycemia. Appl Physiol Nutr Metab 32: 3: 576-582, 2007.

results

p<0.05, insulin users vs. non-insulin users

Table 1. BLOOD GLUCOSE RESPONSES AND INCIDENCE OF HYPOGLYCEMIA

  All Participants Insulin Users Non-Insulin Users

Participants (n) 3,916 3,088 829

Pre-Exercise Blood Glucose (mg/dL) 155.2 ± 0.9 159.2 ± 1.0* 140.4 ± 1.6

Post-Exercise Blood Glucose (mg/dL) 122.6 ± 0.8 124.0 ± 0.9* 117.4 ± 1.4

Change in Blood Glucose (mg/dL) -32.6 ± 0.6 -35.2 ± 0.7* -23.0 ± 1.0

Hypoglycemia (<65 mg/dL) Post-Exercise (n)/(%)

125(3.2%)

121*(3.9%)

4(0.5%)

• Although 89.2% of total participants (ES and SS) experienced a decrease in blood glucose levels following 14 minutes of physical activity, the decrease was significantly greater in insulin users and more of them experienced post-exercise hypoglycemia (p<0.05).

• Comparing across languages/cultures, only 88.5% of ES participants experienced a decrease in blood glucose while 92.8% of SS did, with consistent percentages by culture for insulin and non-insulin users. Hypoglycemic events after BBT participation was also lower in SS.

• Only 0.8% of total participants (23 insulin users and 10 non-insulin users) recorded no change in blood glucose levels post-exercise, whereas 10.0% of insulin users and 10.3% of non-insulin users (391 individuals total) experienced increased levels following BBT participation.

• A slightly smaller percentage (6.4%) of native SS participants experienced an increase in blood glucose, regardless of insulin use, compared to ES participants.

conclusionIn conclusion, the BBT has demonstrated that participation in 14 minutes of varying types of physical activity effectively lowers blood glucose levels in most individuals with diabetes.

Furthermore, although the risk of developing hypoglycemia as the result of such participation is higher in insulin users, less than 4% of all individuals experienced a post-exercise blood glucose level lower than 65 mg/dL.

Some cultural differences may be present in glycemic responses to 14 minutes of physical activity and warrant further investigation.

p<0.05, insulin users vs. non-insulin users

 Table 2. BLOOD GLUCOSE RESPONSES AND INCIDENCE OF HYPOGLYCEMIA

IN ENGLISH-SPEAKING (ES) VS. SPANISH-SPEAKING (SS) PARTICIPANTS

 

  All Participants Insulin Users Non-Insulin Users

ES Participant Number (%)3,263

(83.3% of all)2,639

(80.9% of ES)625

(19.1% of ES)

SS Participant Number (%)653

(16.7% of all)449

(68.8% of SS)204

(31.2% of SS)ES Pre-Exercise Blood Glucose (mg/dL) 156.0 ± 1.0 159.7 ± 1.1* 140.4 ± 1.6

SS Pre-Exercise Blood Glucose (mg/dL) 150.9 ± 2.1 156.0 ± 2.5* 140.1 ± 3.5

ES Post-Exercise Blood Glucose (mg/dL) 123.3 ± 0.9 124.6 ± 1.0* 117.4 ± 1.4

SS Post-Exercise Blood Glucose (mg/dL) 118.9 ± 1.8 119.9 ± 2.2 116.4 ± 2.9

ES Change in Blood Glucose (mg/dL) -32.7 ± 0.7 -35.0 ± 0.8* -23.0 ± 1.0

SS Change in Blood Glucose (mg/dL) -32.0 ± 1.4 -36.1 ± 1.7* -23.7 ± 2.4

ES Hypoglycemia (<65 mg/dL) Post-Exercise Events (%) 114

(3.5%)110*

(4.2%)4

(0.6%)

SS Hypoglycemia (<65 mg/dL) Post-Exercise Events (%) 11

(1.7%)11*

(2.4%)0

(0.0%)

Effects Of 14 Minutes Of Physical Activity On Blood Glucose Levels S.R. Colberg1 (Human Movement Sciences Dept., Old Dominion University), M.J. Hernandez,2 (Diabetes Hands Foundation)

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