Male: (height cm-80) × 70 ~ = standard weight;
Female: (height cm-70) × 60 = standard weight;
Standard weight plus or minus 10% is normal weight;
Standard weight plus or minus 10 ~ 20% overweight or underweight;
Obesity or underweight is defined as plus or minus 20% of standard weight.
Therefore, the standard weight of 169cm boys is: (169-80)x 0.7 = 62.3 kg.